diff --git a/src/ol/collection.js b/src/ol/collection.js
index be85ad78c4..31f7259cef 100644
--- a/src/ol/collection.js
+++ b/src/ol/collection.js
@@ -115,12 +115,12 @@ ol.Collection.prototype.extend = function(arr) {
  * @param {function(this: S, T, number, Array.<T>): *} f The function to call
  *     for every element. This function takes 3 arguments (the element, the
  *     index and the array). The return value is ignored.
- * @param {S=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {S=} opt_this The object to use as `this` in `f`.
  * @template T,S
  * @todo stability experimental
  */
-ol.Collection.prototype.forEach = function(f, opt_obj) {
-  goog.array.forEach(this.array_, f, opt_obj);
+ol.Collection.prototype.forEach = function(f, opt_this) {
+  goog.array.forEach(this.array_, f, opt_this);
 };
 
 
diff --git a/src/ol/map.js b/src/ol/map.js
index fdde46f9b4..074fe22354 100644
--- a/src/ol/map.js
+++ b/src/ol/map.js
@@ -1274,13 +1274,13 @@ ol.Map.prototype.updateSize = function() {
 
 /**
  * @param {function(this: T)} f Function.
- * @param {T=} opt_obj Object.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @template T
  */
-ol.Map.prototype.withFrozenRendering = function(f, opt_obj) {
+ol.Map.prototype.withFrozenRendering = function(f, opt_this) {
   this.freezeRendering();
   try {
-    f.call(opt_obj);
+    f.call(opt_this);
   } finally {
     this.unfreezeRendering();
   }
diff --git a/src/ol/observable.js b/src/ol/observable.js
index 5b20280df6..c3d51b1d24 100644
--- a/src/ol/observable.js
+++ b/src/ol/observable.js
@@ -25,13 +25,12 @@ goog.inherits(ol.Observable, goog.events.EventTarget);
  * Listen for a certain type of event.
  * @param {string|Array.<string>} type The event type or array of event types.
  * @param {function(?): ?} listener The listener function.
- * @param {Object=} opt_scope Object is whose scope to call
- *     the listener.
+ * @param {Object=} opt_this The object to use as `this` in `listener`.
  * @return {goog.events.Key} Unique key for the listener.
  * @todo stability experimental
  */
-ol.Observable.prototype.on = function(type, listener, opt_scope) {
-  return goog.events.listen(this, type, listener, false, opt_scope);
+ol.Observable.prototype.on = function(type, listener, opt_this) {
+  return goog.events.listen(this, type, listener, false, opt_this);
 };
 
 
@@ -39,13 +38,12 @@ ol.Observable.prototype.on = function(type, listener, opt_scope) {
  * Listen once for a certain type of event.
  * @param {string|Array.<string>} type The event type or array of event types.
  * @param {function(?): ?} listener The listener function.
- * @param {Object=} opt_scope Object is whose scope to call
- *     the listener.
+ * @param {Object=} opt_this The object to use as `this` in `listener`.
  * @return {goog.events.Key} Unique key for the listener.
  * @todo stability experimental
  */
-ol.Observable.prototype.once = function(type, listener, opt_scope) {
-  return goog.events.listenOnce(this, type, listener, false, opt_scope);
+ol.Observable.prototype.once = function(type, listener, opt_this) {
+  return goog.events.listenOnce(this, type, listener, false, opt_this);
 };
 
 
@@ -53,12 +51,11 @@ ol.Observable.prototype.once = function(type, listener, opt_scope) {
  * Unlisten for a certain type of event.
  * @param {string|Array.<string>} type The event type or array of event types.
  * @param {function(?): ?} listener The listener function.
- * @param {Object=} opt_scope Object is whose scope to call
- *     the listener.
+ * @param {Object=} opt_this The object to use as `this` in `listener`.
  * @todo stability experimental
  */
-ol.Observable.prototype.un = function(type, listener, opt_scope) {
-  goog.events.unlisten(this, type, listener, false, opt_scope);
+ol.Observable.prototype.un = function(type, listener, opt_this) {
+  goog.events.unlisten(this, type, listener, false, opt_this);
 };
 
 
diff --git a/src/ol/renderer/canvas/canvasimagelayerrenderer.js b/src/ol/renderer/canvas/canvasimagelayerrenderer.js
index a108112034..bf53f5cf9a 100644
--- a/src/ol/renderer/canvas/canvasimagelayerrenderer.js
+++ b/src/ol/renderer/canvas/canvasimagelayerrenderer.js
@@ -45,7 +45,7 @@ goog.inherits(ol.renderer.canvas.ImageLayer, ol.renderer.canvas.Layer);
  * @inheritDoc
  */
 ol.renderer.canvas.ImageLayer.prototype.forEachFeatureAtPixel =
-    function(coordinate, frameState, callback, opt_obj) {
+    function(coordinate, frameState, callback, opt_this) {
   var layer = this.getLayer();
   var source = layer.getSource();
   goog.asserts.assertInstanceof(source, ol.source.Image);
@@ -58,7 +58,7 @@ ol.renderer.canvas.ImageLayer.prototype.forEachFeatureAtPixel =
        * @return {?} Callback result.
        */
       function(feature) {
-        return callback.call(opt_obj, feature, this);
+        return callback.call(opt_this, feature, this);
       });
 };
 
diff --git a/src/ol/renderer/canvas/canvasvectorlayerrenderer.js b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
index 4247864b11..05f4a5a228 100644
--- a/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
+++ b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
@@ -89,7 +89,7 @@ ol.renderer.canvas.VectorLayer.prototype.composeFrame =
  * @inheritDoc
  */
 ol.renderer.canvas.VectorLayer.prototype.forEachFeatureAtPixel =
-    function(coordinate, frameState, callback, opt_obj) {
+    function(coordinate, frameState, callback, opt_this) {
   if (goog.isNull(this.replayGroup_)) {
     return undefined;
   } else {
@@ -109,7 +109,7 @@ ol.renderer.canvas.VectorLayer.prototype.forEachFeatureAtPixel =
         function(geometry, data) {
           var feature = /** @type {ol.Feature} */ (data);
           goog.asserts.assert(goog.isDef(feature));
-          return callback.call(opt_obj, feature, layer);
+          return callback.call(opt_this, feature, layer);
         });
   }
 };
diff --git a/src/ol/renderer/dom/domimagelayerrenderer.js b/src/ol/renderer/dom/domimagelayerrenderer.js
index 2578a0e682..b062dd984c 100644
--- a/src/ol/renderer/dom/domimagelayerrenderer.js
+++ b/src/ol/renderer/dom/domimagelayerrenderer.js
@@ -50,7 +50,7 @@ goog.inherits(ol.renderer.dom.ImageLayer, ol.renderer.dom.Layer);
  * @inheritDoc
  */
 ol.renderer.dom.ImageLayer.prototype.forEachFeatureAtPixel =
-    function(coordinate, frameState, callback, opt_obj) {
+    function(coordinate, frameState, callback, opt_this) {
   var layer = this.getLayer();
   var source = layer.getSource();
   goog.asserts.assertInstanceof(source, ol.source.Image);
@@ -63,7 +63,7 @@ ol.renderer.dom.ImageLayer.prototype.forEachFeatureAtPixel =
        * @return {?} Callback result.
        */
       function(feature) {
-        return callback.call(opt_obj, feature, this);
+        return callback.call(opt_this, feature, this);
       });
 };
 
diff --git a/src/ol/renderer/layerrenderer.js b/src/ol/renderer/layerrenderer.js
index dd7b5af273..dfce3aae5e 100644
--- a/src/ol/renderer/layerrenderer.js
+++ b/src/ol/renderer/layerrenderer.js
@@ -49,7 +49,7 @@ goog.inherits(ol.renderer.Layer, goog.Disposable);
  * @param {ol.FrameState} frameState Frame state.
  * @param {function(this: S, ol.Feature, ol.layer.Layer): T} callback Feature
  *     callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this Object to use as `this` in `callback`.
  * @return {T|undefined} Callback result.
  * @template S,T
  */
@@ -249,13 +249,13 @@ ol.renderer.Layer.prototype.snapCenterToPixel =
  * @param {number} currentZ Current Z.
  * @param {number} preload Load low resolution tiles up to 'preload' levels.
  * @param {function(this: T, ol.Tile)=} opt_tileCallback Tile callback.
- * @param {T=} opt_obj Object.
+ * @param {T=} opt_this Object to use as `this` in `opt_tileCallback`.
  * @protected
  * @template T
  */
 ol.renderer.Layer.prototype.manageTilePyramid = function(
     frameState, tileSource, tileGrid, projection, extent, currentZ, preload,
-    opt_tileCallback, opt_obj) {
+    opt_tileCallback, opt_this) {
   var tileSourceKey = goog.getUid(tileSource).toString();
   if (!(tileSourceKey in frameState.wantedTiles)) {
     frameState.wantedTiles[tileSourceKey] = {};
@@ -279,7 +279,7 @@ ol.renderer.Layer.prototype.manageTilePyramid = function(
             }
           }
           if (goog.isDef(opt_tileCallback)) {
-            opt_tileCallback.call(opt_obj, tile);
+            opt_tileCallback.call(opt_this, tile);
           }
         } else {
           tileSource.useTile(z, x, y);
diff --git a/src/ol/renderer/webgl/webglimagelayerrenderer.js b/src/ol/renderer/webgl/webglimagelayerrenderer.js
index 2fd5c166fd..e2b45f7cbd 100644
--- a/src/ol/renderer/webgl/webglimagelayerrenderer.js
+++ b/src/ol/renderer/webgl/webglimagelayerrenderer.js
@@ -76,7 +76,7 @@ ol.renderer.webgl.ImageLayer.prototype.createTexture_ = function(image) {
  * @inheritDoc
  */
 ol.renderer.webgl.ImageLayer.prototype.forEachFeatureAtPixel =
-    function(coordinate, frameState, callback, opt_obj) {
+    function(coordinate, frameState, callback, opt_this) {
   var layer = this.getLayer();
   var source = layer.getSource();
   goog.asserts.assertInstanceof(source, ol.source.Image);
@@ -89,7 +89,7 @@ ol.renderer.webgl.ImageLayer.prototype.forEachFeatureAtPixel =
        * @return {?} Callback result.
        */
       function(feature) {
-        return callback.call(opt_obj, feature, this);
+        return callback.call(opt_this, feature, this);
       });
 };
 
diff --git a/src/ol/source/vectorsource.js b/src/ol/source/vectorsource.js
index 4f0154ed09..b08834df8a 100644
--- a/src/ol/source/vectorsource.js
+++ b/src/ol/source/vectorsource.js
@@ -140,30 +140,30 @@ ol.source.Vector.prototype.clear = function() {
 
 /**
  * @param {function(this: T, ol.Feature): S} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @return {S|undefined}
  * @template T,S
  */
-ol.source.Vector.prototype.forEachFeature = function(f, opt_obj) {
-  return this.rBush_.forEach(f, opt_obj);
+ol.source.Vector.prototype.forEachFeature = function(f, opt_this) {
+  return this.rBush_.forEach(f, opt_this);
 };
 
 
 /**
  * @param {ol.Coordinate} coordinate Coordinate.
  * @param {function(this: T, ol.Feature): S} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @return {S|undefined}
  * @template T,S
  */
 ol.source.Vector.prototype.forEachFeatureAtCoordinate =
-    function(coordinate, f, opt_obj) {
+    function(coordinate, f, opt_this) {
   var extent = [coordinate[0], coordinate[1], coordinate[0], coordinate[1]];
   return this.forEachFeatureInExtent(extent, function(feature) {
     var geometry = feature.getGeometry();
     goog.asserts.assert(!goog.isNull(geometry));
     if (geometry.containsCoordinate(coordinate)) {
-      return f.call(opt_obj, feature);
+      return f.call(opt_this, feature);
     } else {
       return undefined;
     }
@@ -174,13 +174,13 @@ ol.source.Vector.prototype.forEachFeatureAtCoordinate =
 /**
  * @param {ol.Extent} extent Extent.
  * @param {function(this: T, ol.Feature): S} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @return {S|undefined}
  * @template T,S
  */
 ol.source.Vector.prototype.forEachFeatureInExtent =
-    function(extent, f, opt_obj) {
-  return this.rBush_.forEachInExtent(extent, f, opt_obj);
+    function(extent, f, opt_this) {
+  return this.rBush_.forEachInExtent(extent, f, opt_this);
 };
 
 
diff --git a/src/ol/structs/buffer.js b/src/ol/structs/buffer.js
index b18052ffe3..cace303348 100644
--- a/src/ol/structs/buffer.js
+++ b/src/ol/structs/buffer.js
@@ -126,12 +126,12 @@ ol.structs.Buffer.prototype.addDirtySet = function(dirtySet) {
 
 /**
  * @param {function(this: T, number, number)} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @template T
  */
-ol.structs.Buffer.prototype.forEachRange = function(f, opt_obj) {
+ol.structs.Buffer.prototype.forEachRange = function(f, opt_this) {
   if (this.arr_.length !== 0) {
-    this.freeSet_.forEachRangeInverted(0, this.arr_.length, f, opt_obj);
+    this.freeSet_.forEachRangeInverted(0, this.arr_.length, f, opt_this);
   }
 };
 
diff --git a/src/ol/structs/integerset.js b/src/ol/structs/integerset.js
index dc292443eb..de716c6842 100644
--- a/src/ol/structs/integerset.js
+++ b/src/ol/structs/integerset.js
@@ -126,15 +126,15 @@ ol.structs.IntegerSet.prototype.findRange = function(minSize) {
 /**
  * Calls f with each integer range.
  * @param {function(this: T, number, number)} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @template T
  */
-ol.structs.IntegerSet.prototype.forEachRange = function(f, opt_obj) {
+ol.structs.IntegerSet.prototype.forEachRange = function(f, opt_this) {
   var arr = this.arr_;
   var n = arr.length;
   var i;
   for (i = 0; i < n; i += 2) {
-    f.call(opt_obj, arr[i], arr[i + 1]);
+    f.call(opt_this, arr[i], arr[i + 1]);
   }
 };
 
@@ -144,26 +144,26 @@ ol.structs.IntegerSet.prototype.forEachRange = function(f, opt_obj) {
  * @param {number} start Start.
  * @param {number} stop Stop.
  * @param {function(this: T, number, number)} f Callback.
- * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {T=} opt_this The object to use as `this` in `f`.
  * @template T
  */
 ol.structs.IntegerSet.prototype.forEachRangeInverted =
-    function(start, stop, f, opt_obj) {
+    function(start, stop, f, opt_this) {
   goog.asserts.assert(start < stop);
   var arr = this.arr_;
   var n = arr.length;
   if (n === 0) {
-    f.call(opt_obj, start, stop);
+    f.call(opt_this, start, stop);
   } else {
     if (start < arr[0]) {
-      f.call(opt_obj, start, arr[0]);
+      f.call(opt_this, start, arr[0]);
     }
     var i;
     for (i = 1; i < n - 1; i += 2) {
-      f.call(opt_obj, arr[i], arr[i + 1]);
+      f.call(opt_this, arr[i], arr[i + 1]);
     }
     if (arr[n - 1] < stop) {
-      f.call(opt_obj, arr[n - 1], stop);
+      f.call(opt_this, arr[n - 1], stop);
     }
   }
 };
diff --git a/src/ol/structs/lrucache.js b/src/ol/structs/lrucache.js
index 3fc7a2427d..e5fecc8d2e 100644
--- a/src/ol/structs/lrucache.js
+++ b/src/ol/structs/lrucache.js
@@ -102,13 +102,13 @@ ol.structs.LRUCache.prototype.containsKey = function(key) {
  *     to call for every entry from the oldest to the newer. This function takes
  *     3 arguments (the entry value, the entry key and the LRUCache object).
  *     The return value is ignored.
- * @param {S=} opt_obj The object to be used as the value of 'this' within f.
+ * @param {S=} opt_this The object to use as `this` in `f`.
  * @template S
  */
-ol.structs.LRUCache.prototype.forEach = function(f, opt_obj) {
+ol.structs.LRUCache.prototype.forEach = function(f, opt_this) {
   var entry = this.oldest_;
   while (!goog.isNull(entry)) {
-    f.call(opt_obj, entry.value_, entry.key_, this);
+    f.call(opt_this, entry.value_, entry.key_, this);
     entry = entry.newer;
   }
 };
diff --git a/src/ol/structs/rbush.js b/src/ol/structs/rbush.js
index bebf1ac470..25437e1056 100644
--- a/src/ol/structs/rbush.js
+++ b/src/ol/structs/rbush.js
@@ -361,20 +361,20 @@ ol.structs.RBush.prototype.condense_ = function(path) {
  * Calls a callback function with each node in the tree. Inside the callback,
  * no tree modifications (insert, update, remove) can be made.
  * @param {function(this: S, T): *} callback Callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this The object to use as `this` in `callback`.
  * @return {*} Callback return value.
  * @template S
  */
-ol.structs.RBush.prototype.forEach = function(callback, opt_obj) {
+ol.structs.RBush.prototype.forEach = function(callback, opt_this) {
   if (goog.DEBUG) {
     ++this.readers_;
     try {
-      return this.forEach_(this.root_, callback, opt_obj);
+      return this.forEach_(this.root_, callback, opt_this);
     } finally {
       --this.readers_;
     }
   } else {
-    return this.forEach_(this.root_, callback, opt_obj);
+    return this.forEach_(this.root_, callback, opt_this);
   }
 };
 
@@ -382,12 +382,12 @@ ol.structs.RBush.prototype.forEach = function(callback, opt_obj) {
 /**
  * @param {ol.structs.RBushNode.<T>} node Node.
  * @param {function(this: S, T): *} callback Callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this The object to use as `this` in `callback`.
  * @private
  * @return {*} Callback return value.
  * @template S
  */
-ol.structs.RBush.prototype.forEach_ = function(node, callback, opt_obj) {
+ol.structs.RBush.prototype.forEach_ = function(node, callback, opt_this) {
   goog.asserts.assert(!node.isLeaf());
   /** @type {Array.<ol.structs.RBushNode.<T>>} */
   var toVisit = [node];
@@ -397,7 +397,7 @@ ol.structs.RBush.prototype.forEach_ = function(node, callback, opt_obj) {
     children = node.children;
     if (node.height == 1) {
       for (i = 0, ii = children.length; i < ii; ++i) {
-        result = callback.call(opt_obj, children[i].value);
+        result = callback.call(opt_this, children[i].value);
         if (result) {
           return result;
         }
@@ -414,21 +414,21 @@ ol.structs.RBush.prototype.forEach_ = function(node, callback, opt_obj) {
  * callback, no tree modifications (insert, update, remove) can be made.
  * @param {ol.Extent} extent Extent.
  * @param {function(this: S, T): *} callback Callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this The object to use as `this` in `callback`.
  * @return {*} Callback return value.
  * @template S
  */
 ol.structs.RBush.prototype.forEachInExtent =
-    function(extent, callback, opt_obj) {
+    function(extent, callback, opt_this) {
   if (goog.DEBUG) {
     ++this.readers_;
     try {
-      return this.forEachInExtent_(extent, callback, opt_obj);
+      return this.forEachInExtent_(extent, callback, opt_this);
     } finally {
       --this.readers_;
     }
   } else {
-    return this.forEachInExtent_(extent, callback, opt_obj);
+    return this.forEachInExtent_(extent, callback, opt_this);
   }
 };
 
@@ -436,13 +436,13 @@ ol.structs.RBush.prototype.forEachInExtent =
 /**
  * @param {ol.Extent} extent Extent.
  * @param {function(this: S, T): *} callback Callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this The object to use as `this` in `callback`.
  * @private
  * @return {*} Callback return value.
  * @template S
  */
 ol.structs.RBush.prototype.forEachInExtent_ =
-    function(extent, callback, opt_obj) {
+    function(extent, callback, opt_this) {
   /** @type {Array.<ol.structs.RBushNode.<T>>} */
   var toVisit = [this.root_];
   var result;
@@ -450,12 +450,12 @@ ol.structs.RBush.prototype.forEachInExtent_ =
     var node = toVisit.pop();
     if (ol.extent.intersects(extent, node.extent)) {
       if (node.isLeaf()) {
-        result = callback.call(opt_obj, node.value);
+        result = callback.call(opt_this, node.value);
         if (result) {
           return result;
         }
       } else if (ol.extent.containsExtent(extent, node.extent)) {
-        result = this.forEach_(node, callback, opt_obj);
+        result = this.forEach_(node, callback, opt_this);
         if (result) {
           return result;
         }
@@ -470,16 +470,16 @@ ol.structs.RBush.prototype.forEachInExtent_ =
 
 /**
  * @param {function(this: S, ol.structs.RBushNode.<T>): *} callback Callback.
- * @param {S=} opt_obj Scope.
+ * @param {S=} opt_this The object to use as `this` in `callback`.
  * @return {*} Callback return value.
  * @template S
  */
-ol.structs.RBush.prototype.forEachNode = function(callback, opt_obj) {
+ol.structs.RBush.prototype.forEachNode = function(callback, opt_this) {
   /** @type {Array.<ol.structs.RBushNode.<T>>} */
   var toVisit = [this.root_];
   while (toVisit.length > 0) {
     var node = toVisit.pop();
-    var result = callback.call(opt_obj, node);
+    var result = callback.call(opt_this, node);
     if (result) {
       return result;
     }
diff --git a/src/ol/tilegrid/tilegrid.js b/src/ol/tilegrid/tilegrid.js
index 1f90552a56..b0aa02212a 100644
--- a/src/ol/tilegrid/tilegrid.js
+++ b/src/ol/tilegrid/tilegrid.js
@@ -115,18 +115,18 @@ ol.tilegrid.TileGrid.prototype.createTileCoordTransform = goog.abstractMethod;
 /**
  * @param {ol.TileCoord} tileCoord Tile coordinate.
  * @param {function(this: T, number, ol.TileRange): boolean} callback Callback.
- * @param {T=} opt_obj Object.
+ * @param {T=} opt_this The object to use as `this` in `callback`.
  * @param {ol.TileRange=} opt_tileRange Temporary ol.TileRange object.
  * @param {ol.Extent=} opt_extent Temporary ol.Extent object.
  * @return {boolean} Callback succeeded.
  * @template T
  */
 ol.tilegrid.TileGrid.prototype.forEachTileCoordParentTileRange =
-    function(tileCoord, callback, opt_obj, opt_tileRange, opt_extent) {
+    function(tileCoord, callback, opt_this, opt_tileRange, opt_extent) {
   var tileCoordExtent = this.getTileCoordExtent(tileCoord, opt_extent);
   var z = tileCoord.z - 1;
   while (z >= this.minZoom) {
-    if (callback.call(opt_obj, z,
+    if (callback.call(opt_this, z,
         this.getTileRangeForExtentAndZ(tileCoordExtent, z, opt_tileRange))) {
       return true;
     }
diff --git a/src/ol/tilegrid/xyztilegrid.js b/src/ol/tilegrid/xyztilegrid.js
index fba719b2ae..d3bdd82d6b 100644
--- a/src/ol/tilegrid/xyztilegrid.js
+++ b/src/ol/tilegrid/xyztilegrid.js
@@ -114,14 +114,14 @@ ol.tilegrid.XYZ.prototype.getTileCoordChildTileRange =
  * @inheritDoc
  */
 ol.tilegrid.XYZ.prototype.forEachTileCoordParentTileRange =
-    function(tileCoord, callback, opt_obj, opt_tileRange) {
+    function(tileCoord, callback, opt_this, opt_tileRange) {
   var tileRange = ol.TileRange.createOrUpdate(
       0, tileCoord.x, 0, tileCoord.y, opt_tileRange);
   var z;
   for (z = tileCoord.z - 1; z >= this.minZoom; --z) {
     tileRange.minX = tileRange.maxX >>= 1;
     tileRange.minY = tileRange.maxY >>= 1;
-    if (callback.call(opt_obj, z, tileRange)) {
+    if (callback.call(opt_this, z, tileRange)) {
       return true;
     }
   }
diff --git a/src/ol/xml.js b/src/ol/xml.js
index 05d5e496e5..8ad47df4bc 100644
--- a/src/ol/xml.js
+++ b/src/ol/xml.js
@@ -51,18 +51,18 @@ ol.xml.getAllTextContent_ = function(node, normalizeWhitespace, accumulator) {
 /**
  * @param {function(this: T, Node, Array.<*>): (Array.<*>|undefined)}
  *     valueReader Value reader.
- * @param {T=} opt_obj Scope.
+ * @param {T=} opt_this The object to use as `this` in `valueReader`.
  * @return {ol.xml.Parser} Parser.
  * @template T
  */
-ol.xml.makeArrayExtender = function(valueReader, opt_obj) {
+ol.xml.makeArrayExtender = function(valueReader, opt_this) {
   return (
       /**
        * @param {Node} node Node.
        * @param {Array.<*>} objectStack Object stack.
        */
       function(node, objectStack) {
-        var value = valueReader.call(opt_obj, node, objectStack);
+        var value = valueReader.call(opt_this, node, objectStack);
         if (goog.isDef(value)) {
           goog.asserts.assert(goog.isArray(value));
           var array = /** @type {Array.<*>} */
@@ -76,18 +76,18 @@ ol.xml.makeArrayExtender = function(valueReader, opt_obj) {
 
 /**
  * @param {function(this: T, Node, Array.<*>): *} valueReader Value reader.
- * @param {T=} opt_obj Scope.
+ * @param {T=} opt_this The object to use as `this` in `valueReader`.
  * @return {ol.xml.Parser} Parser.
  * @template T
  */
-ol.xml.makeArrayPusher = function(valueReader, opt_obj) {
+ol.xml.makeArrayPusher = function(valueReader, opt_this) {
   return (
       /**
        * @param {Node} node Node.
        * @param {Array.<*>} objectStack Object stack.
        */
       function(node, objectStack) {
-        var value = valueReader.call(opt_obj, node, objectStack);
+        var value = valueReader.call(opt_this, node, objectStack);
         if (goog.isDef(value)) {
           var array = objectStack[objectStack.length - 1];
           goog.asserts.assert(goog.isArray(array));
@@ -99,18 +99,18 @@ ol.xml.makeArrayPusher = function(valueReader, opt_obj) {
 
 /**
  * @param {function(this: T, Node, Array.<*>): *} valueReader Value reader.
- * @param {T=} opt_obj Scope.
+ * @param {T=} opt_this The object to use as `this` in `valueReader`.
  * @return {ol.xml.Parser} Parser.
  * @template T
  */
-ol.xml.makeReplacer = function(valueReader, opt_obj) {
+ol.xml.makeReplacer = function(valueReader, opt_this) {
   return (
       /**
        * @param {Node} node Node.
        * @param {Array.<*>} objectStack Object stack.
        */
       function(node, objectStack) {
-        var value = valueReader.call(opt_obj, node, objectStack);
+        var value = valueReader.call(opt_this, node, objectStack);
         if (goog.isDef(value)) {
           objectStack[objectStack.length - 1] = value;
         }
@@ -121,11 +121,12 @@ ol.xml.makeReplacer = function(valueReader, opt_obj) {
 /**
  * @param {function(this: T, Node, Array.<*>): *} valueReader Value reader.
  * @param {string=} opt_property Property.
- * @param {T=} opt_obj Scope.
+ * @param {T=} opt_this The object to use as `this` in `valueReader`.
  * @return {ol.xml.Parser} Parser.
  * @template T
  */
-ol.xml.makeObjectPropertySetter = function(valueReader, opt_property, opt_obj) {
+ol.xml.makeObjectPropertySetter =
+    function(valueReader, opt_property, opt_this) {
   goog.asserts.assert(goog.isDef(valueReader));
   return (
       /**
@@ -133,7 +134,7 @@ ol.xml.makeObjectPropertySetter = function(valueReader, opt_property, opt_obj) {
        * @param {Array.<*>} objectStack Object stack.
        */
       function(node, objectStack) {
-        var value = valueReader.call(opt_obj, node, objectStack);
+        var value = valueReader.call(opt_this, node, objectStack);
         if (goog.isDef(value)) {
           var object = /** @type {Object} */
               (objectStack[objectStack.length - 1]);
@@ -169,16 +170,16 @@ ol.xml.makeParsersNS = function(namespaceURIs, parsers, opt_parsersNS) {
  *     Parsers by namespace.
  * @param {Node} node Node.
  * @param {Array.<*>} objectStack Object stack.
- * @param {*=} opt_obj Scope.
+ * @param {*=} opt_this The object to use as `this`.
  */
-ol.xml.parse = function(parsersNS, node, objectStack, opt_obj) {
+ol.xml.parse = function(parsersNS, node, objectStack, opt_this) {
   var n;
   for (n = node.firstElementChild; !goog.isNull(n); n = n.nextElementSibling) {
     var parsers = parsersNS[n.namespaceURI];
     if (goog.isDef(parsers)) {
       var parser = parsers[n.localName];
       if (goog.isDef(parser)) {
-        parser.call(opt_obj, n, objectStack);
+        parser.call(opt_this, n, objectStack);
       }
     }
   }
@@ -191,12 +192,12 @@ ol.xml.parse = function(parsersNS, node, objectStack, opt_obj) {
  *     Parsers by namespace.
  * @param {Node} node Node.
  * @param {Array.<*>} objectStack Object stack.
- * @param {*=} opt_obj Scope.
+ * @param {*=} opt_this The object to use as `this`.
  * @return {T|undefined} Object.
  * @template T
  */
-ol.xml.pushAndParse = function(object, parsersNS, node, objectStack, opt_obj) {
+ol.xml.pushAndParse = function(object, parsersNS, node, objectStack, opt_this) {
   objectStack.push(object);
-  ol.xml.parse(parsersNS, node, objectStack, opt_obj);
+  ol.xml.parse(parsersNS, node, objectStack, opt_this);
   return objectStack.pop();
 };