diff --git a/reference/spl/functions/class-implements.xml b/reference/spl/functions/class-implements.xml
index 47307580d2..75652f63eb 100644
--- a/reference/spl/functions/class-implements.xml
+++ b/reference/spl/functions/class-implements.xml
@@ -4,7 +4,7 @@
  <refnamediv>
   <refname>class_implements</refname>
   <refpurpose>
-   Return the interfaces which are implemented by the given class
+   Return the interfaces which are implemented by the given class or interface
   </refpurpose>
  </refnamediv>
  <refsect1 role="description">
@@ -28,7 +28,7 @@
      <term><parameter>class</parameter></term>
      <listitem>
       <para>
-       An object (class instance) or a string (class name).
+       An object (class instance) or a string (class or interface name).
       </para>
      </listitem>
     </varlistentry>