diff --git a/src/os_macosx.m b/src/os_macosx.m
index 84a0def..33d29b6 100644
--- a/src/os_macosx.m
+++ b/src/os_macosx.m
@@ -334,7 +334,7 @@
  *
  * The limitations and differences include:
  *
- * - The flags argument is ignored. The supplied new_value is therfore
+ * - The flags argument is ignored. The supplied new_value is therefore
  *   always treated as a relative time.
  * - The old_value argument is ignored.
  */