diff --git a/os/rt/src/chmtx.c b/os/rt/src/chmtx.c
index 899e04d1b..8b11250e0 100644
--- a/os/rt/src/chmtx.c
+++ b/os/rt/src/chmtx.c
@@ -376,7 +376,7 @@ void chMtxUnlock(mutex_t *mp) {
       mp->next = tp->mtxlist;
       tp->mtxlist = mp;
 
-      /* Note, not using chSchWakeupS() becuase that function expects the
+      /* Note, not using chSchWakeupS() because that function expects the
          current thread to have the higher or equal priority than the ones
          in the ready list. This is not necessarily true here because we
          just changed priority.*/