diff --git a/mempool/mempool.go b/mempool/mempool.go
index 75dc13df55b..6a6a2c3c3d8 100644
--- a/mempool/mempool.go
+++ b/mempool/mempool.go
@@ -31,7 +31,7 @@ const (
 type Mempool interface {
 	// CheckTx executes a new transaction against the application to determine
 	// its validity and whether it should be added to the mempool.
-	CheckTxSync(tx types.Tx, cb func(*abci.ResponseCheckTx), txInfo TxInfo) (*abci.ResponseCheckTx, error)
+	CheckTxSync(tx types.Tx, callback func(*abci.ResponseCheckTx), txInfo TxInfo) (*abci.ResponseCheckTx, error)
 	CheckTxAsync(tx types.Tx, txInfo TxInfo, prepareCb func(error), checkTxCb func(*abci.ResponseCheckTx))
 
 	// RemoveTxByKey removes a transaction, identified by its key,
diff --git a/test/fuzz/mempool/checktx.go b/test/fuzz/mempool/checktx.go
index 0120248da6a..36ea6ea1524 100644
--- a/test/fuzz/mempool/checktx.go
+++ b/test/fuzz/mempool/checktx.go
@@ -24,7 +24,7 @@ func init() {
 }
 
 func Fuzz(data []byte) int {
-	_, err := mempool.CheckTxSync(data, mempl.TxInfo{})
+	_, err := mempool.CheckTxSync(data, nil, mempl.TxInfo{})
 	if err != nil {
 		return 0
 	}
diff --git a/test/fuzz/tests/mempool_test.go b/test/fuzz/tests/mempool_test.go
index ac5ffd347e8..5c73d69fd1f 100644
--- a/test/fuzz/tests/mempool_test.go
+++ b/test/fuzz/tests/mempool_test.go
@@ -27,6 +27,6 @@ func FuzzMempool(f *testing.F) {
 	mp := mempool.NewCListMempool(cfg, conn, 0)
 
 	f.Fuzz(func(t *testing.T, data []byte) {
-		_, _ = mp.CheckTxSync(data, mempool.TxInfo{})
+		_, _ = mp.CheckTxSync(data, nil, mempool.TxInfo{})
 	})
 }