diff --git a/src/os/unix/ngx_thread_mutex.c b/src/os/unix/ngx_thread_mutex.c
index 6e8385e..a0ef693 100644
--- a/src/os/unix/ngx_thread_mutex.c
+++ b/src/os/unix/ngx_thread_mutex.c
@@ -49,7 +49,7 @@
  *             for each mutex from 10 to 100 based on spin count taken
  *             previously.
  *   FreeBSD:  Deadlock detection.  The default spin count is 2000.
- *             It can be overriden using LIBPTHREAD_SPINLOOPS environment
+ *             It can be overridden using LIBPTHREAD_SPINLOOPS environment
  *             variable or by pthread_mutex_setspinloops_np().  If a lock
  *             is still busy, sched_yield() can be called on both UP and
  *             SMP systems.  The default yield loop count is zero, but