diff --git a/src/ol/extent.js b/src/ol/extent.js
index dee6c57968..dc937c2df2 100644
--- a/src/ol/extent.js
+++ b/src/ol/extent.js
@@ -70,8 +70,7 @@ ol.extent.containsCoordinate = function(extent, coordinate) {
 
 
 /**
- * Checks if the passed extent is contained or on the edge of the
- * extent.
+ * Checks if `extent2` is contained by or on the edge of `extent1`.
  *
  * @param {ol.Extent} extent1 Extent 1.
  * @param {ol.Extent} extent2 Extent 2.