diff --git a/solr/core/src/java/org/apache/solr/update/processor/FieldMutatingUpdateProcessorFactory.java b/solr/core/src/java/org/apache/solr/update/processor/FieldMutatingUpdateProcessorFactory.java
index 249cf0b28ff..01b0f536e3c 100644
--- a/solr/core/src/java/org/apache/solr/update/processor/FieldMutatingUpdateProcessorFactory.java
+++ b/solr/core/src/java/org/apache/solr/update/processor/FieldMutatingUpdateProcessorFactory.java
@@ -242,7 +242,7 @@ public abstract class FieldMutatingUpdateProcessorFactory
 
   /**
    * Removes all instance of the key from NamedList, returning the Set of 
-   * Strings that key refered to.  Throws an error if the key didn't refer 
+   * Strings that key referred to.  Throws an error if the key didn't refer
    * to one or more strings (or arrays of strings)
    * @exception SolrException invalid arr/str structure.
    */