diff --git a/src/test/coins_tests.cpp b/src/test/coins_tests.cpp
index 97fe5a167..4ff101d08 100644
--- a/src/test/coins_tests.cpp
+++ b/src/test/coins_tests.cpp
@@ -47,9 +47,9 @@ public:
         }
     }
 
-    bool GetNullifier(const uint256 &serial) const
+    bool GetNullifier(const uint256 &nf) const
     {
-        std::map<uint256, bool>::const_iterator it = mapNullifiers_.find(serial);
+        std::map<uint256, bool>::const_iterator it = mapNullifiers_.find(nf);
 
         if (it == mapNullifiers_.end()) {
             return false;