diff --git a/include/nuttx/clock.h b/include/nuttx/clock.h
index 6bd47db65b0..2be054cc4fd 100644
--- a/include/nuttx/clock.h
+++ b/include/nuttx/clock.h
@@ -133,7 +133,10 @@
 #define MSEC_PER_HOUR          (MSEC_PER_MIN * MIN_PER_HOUR)
 #define DSEC_PER_HOUR          (HSEC_PER_SEC * MIN_PER_HOUR)
 #define HSEC_PER_HOUR          (DSEC_PER_MIN * MIN_PER_HOUR)
-#define SEC_PER_HOUR           (SEC_PER_MIN * MIN_PER_HOUR)
+#define SEC_PER_HOUR           (SEC_PER_MIN  * MIN_PER_HOUR)
+
+#define HOURS_PER_DAY                 24L
+#define SEC_PER_DAY            (HOURS_PER_DAY * SEC_PER_HOUR)
 
 /* If CONFIG_SCHED_TICKLESS is not defined, then the interrupt interval of
  * the system timer is given by USEC_PER_TICK.  This is the expected number
diff --git a/sched/clock/clock_initialize.c b/sched/clock/clock_initialize.c
index 6cdf1b3a81a..35a1904ed6f 100644
--- a/sched/clock/clock_initialize.c
+++ b/sched/clock/clock_initialize.c
@@ -1,7 +1,8 @@
 /****************************************************************************
  * sched/clock/clock_initialize.c
  *
- *   Copyright (C) 2007, 2009, 2011-2012, 2017 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2009, 2011-2012, 2017-2018 Gregory Nutt. All rights
+ *     reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -58,16 +59,6 @@
 #  include "clock/clock_timekeeping.h"
 #endif
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/* Standard time definitions (in units of seconds) */
-
-#define SEC_PER_MIN  ((time_t)60)
-#define SEC_PER_HOUR ((time_t)60 * SEC_PER_MIN)
-#define SEC_PER_DAY  ((time_t)24 * SEC_PER_HOUR)
-
 /****************************************************************************
  * Public Data
  ****************************************************************************/