diff --git a/ev.c b/ev.c
index 7d2e240..0095f5c 100644
--- a/ev.c
+++ b/ev.c
@@ -546,7 +546,7 @@ struct signalfd_siginfo
    : 0 < (time_t)4294967295 ?     4294967295.  \
    :                              2147483647.) \
 
-#define EV_TS_TO_MS(a) a * 1e3 + 0.9999
+#define EV_TS_TO_MSEC(a) a * 1e3 + 0.9999
 #define EV_TS_FROM_USEC(us) us * 1e-6
 #define EV_TV_SET(tv,t) do { tv.tv_sec = (long)t; tv.tv_usec = (long)((t - tv.tv_sec) * 1e6); } while (0)
 #define EV_TS_SET(ts,t) do { ts.tv_sec = (long)t; ts.tv_nsec = (long)((t - ts.tv_sec) * 1e9); } while (0)
@@ -2045,7 +2045,7 @@ ev_sleep (ev_tstamp delay) EV_NOEXCEPT
 #elif defined _WIN32
       /* maybe this should round up, as ms is very low resolution */
       /* compared to select (µs) or nanosleep (ns) */
-      Sleep ((unsigned long)(EV_TS_TO_MS (delay)));
+      Sleep ((unsigned long)(EV_TS_TO_MSEC (delay)));
 #else
       struct timeval tv;
 
diff --git a/ev_epoll.c b/ev_epoll.c
index 1832ec8..52b458d 100644
--- a/ev_epoll.c
+++ b/ev_epoll.c
@@ -152,7 +152,7 @@ epoll_poll (EV_P_ ev_tstamp timeout)
   /* epoll wait times cannot be larger than (LONG_MAX - 999UL) / HZ msecs, which is below */
   /* the default libev max wait time, however. */
   EV_RELEASE_CB;
-  eventcnt = epoll_wait (backend_fd, epoll_events, epoll_eventmax, EV_TS_TO_MS (timeout));
+  eventcnt = epoll_wait (backend_fd, epoll_events, epoll_eventmax, EV_TS_TO_MSEC (timeout));
   EV_ACQUIRE_CB;
 
   if (ecb_expect_false (eventcnt < 0))
diff --git a/ev_poll.c b/ev_poll.c
index e6d3202..a106d3d 100644
--- a/ev_poll.c
+++ b/ev_poll.c
@@ -95,7 +95,7 @@ poll_poll (EV_P_ ev_tstamp timeout)
   int res;
   
   EV_RELEASE_CB;
-  res = poll (polls, pollcnt, EV_TS_TO_MS (timeout));
+  res = poll (polls, pollcnt, EV_TS_TO_MSEC (timeout));
   EV_ACQUIRE_CB;
 
   if (ecb_expect_false (res < 0))