diff --git a/system_state.h b/system_state.h
index 4dee1eb..a04c434 100644
--- a/system_state.h
+++ b/system_state.h
@@ -102,7 +102,7 @@
   Prefs prefs_;
 
   // All state pertaining to payload state such as
-  // response, URL, back-off states.
+  // response, URL, backoff states.
   PayloadState payload_state_;
 };