diff --git a/src/main/scala/scalatutorial/sections/ObjectOrientedProgramming.scala b/src/main/scala/scalatutorial/sections/ObjectOrientedProgramming.scala
index c9df0a2b..4f261118 100644
--- a/src/main/scala/scalatutorial/sections/ObjectOrientedProgramming.scala
+++ b/src/main/scala/scalatutorial/sections/ObjectOrientedProgramming.scala
@@ -499,7 +499,7 @@ object ObjectOrientedProgramming extends ScalaTutorialSection {
    *
    * The definitions of `contains` and `incl` in the classes
    * `Empty` and `NonEmpty` ''implement'' the abstract
-   * functions in the base trait `IntSet`.
+   * functions in the base class `IntSet`.
    *
    * It is also possible to ''redefine'' an existing, non-abstract
    * definition in a subclass by using `override`.