diff --git a/eth/backend.go b/eth/backend.go
index 38c0fa974..b99ae7655 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -387,7 +387,7 @@ func (s *Ethereum) shouldPreserve(header *types.Header) bool {
 	// r5   A      [X] F G
 	// r6    [X]
 	//
-	// In the round5, the inturn signer E is offline, so the worst case
+	// In the round5, the in-turn signer E is offline, so the worst case
 	// is A, F and G sign the block of round5 and reject the block of opponents
 	// and in the round6, the last available signer B is offline, the whole
 	// network is stuck.