diff --git a/doc/unordered/concurrent.adoc b/doc/unordered/concurrent.adoc
index aed9c466..7ed1be44 100644
--- a/doc/unordered/concurrent.adoc
+++ b/doc/unordered/concurrent.adoc
@@ -158,7 +158,7 @@ Traversal can be interrupted midway:
 
 [source,c++]
 ----
-// finds the key to a given (unique value)
+// finds the key to a given (unique) value
 
 int  key = 0;
 int  value = ...;