diff --git a/core/dive.h b/core/dive.h
index 09ef61b42..a38236fc5 100644
--- a/core/dive.h
+++ b/core/dive.h
@@ -204,8 +204,6 @@ extern void invalidate_dive_cache(struct dive *dc);
 extern void set_autogroup(bool value);
 extern int total_weight(const struct dive *);
 
-const char *monthname(int mon);
-
 extern const char *existing_filename;
 
 extern bool has_planned(const struct dive *dive, bool planned);
diff --git a/core/subsurface-time.h b/core/subsurface-time.h
index 8d564753f..828a8ef02 100644
--- a/core/subsurface-time.h
+++ b/core/subsurface-time.h
@@ -18,6 +18,8 @@ extern int utc_weekday(timestamp_t timestamp);
 extern timestamp_t parse_datetime(const char *s); /* returns 0 on error */
 extern char *format_datetime(timestamp_t timestamp); /* ownership of string passed to caller */
 
+extern const char *monthname(int mon);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/core/subsurfacestartup.c b/core/subsurfacestartup.c
index c2e4dda04..23e17c7a7 100644
--- a/core/subsurfacestartup.c
+++ b/core/subsurfacestartup.c
@@ -115,16 +115,6 @@ const struct units *get_units()
 	return &prefs.units;
 }
 
-/* random helper functions, used here or elsewhere */
-const char *monthname(int mon)
-{
-	static const char month_array[12][4] = {
-		QT_TRANSLATE_NOOP("gettextFromC", "Jan"), QT_TRANSLATE_NOOP("gettextFromC", "Feb"), QT_TRANSLATE_NOOP("gettextFromC", "Mar"), QT_TRANSLATE_NOOP("gettextFromC", "Apr"), QT_TRANSLATE_NOOP("gettextFromC", "May"), QT_TRANSLATE_NOOP("gettextFromC", "Jun"),
-		QT_TRANSLATE_NOOP("gettextFromC", "Jul"), QT_TRANSLATE_NOOP("gettextFromC", "Aug"), QT_TRANSLATE_NOOP("gettextFromC", "Sep"), QT_TRANSLATE_NOOP("gettextFromC", "Oct"), QT_TRANSLATE_NOOP("gettextFromC", "Nov"), QT_TRANSLATE_NOOP("gettextFromC", "Dec"),
-	};
-	return translate("gettextFromC", month_array[mon]);
-}
-
 /*
  * track whether we switched to importing dives
  */
diff --git a/core/time.c b/core/time.c
index d5196e868..861d7b1d5 100644
--- a/core/time.c
+++ b/core/time.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "subsurface-time.h"
 #include "subsurface-string.h"
+#include "gettext.h"
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -213,3 +214,13 @@ extern char *format_datetime(timestamp_t timestamp)
 
 	return strdup(buf);
 }
+
+/* Turn month (0-12) into three-character short name */
+const char *monthname(int mon)
+{
+	static const char month_array[12][4] = {
+		QT_TRANSLATE_NOOP("gettextFromC", "Jan"), QT_TRANSLATE_NOOP("gettextFromC", "Feb"), QT_TRANSLATE_NOOP("gettextFromC", "Mar"), QT_TRANSLATE_NOOP("gettextFromC", "Apr"), QT_TRANSLATE_NOOP("gettextFromC", "May"), QT_TRANSLATE_NOOP("gettextFromC", "Jun"),
+		QT_TRANSLATE_NOOP("gettextFromC", "Jul"), QT_TRANSLATE_NOOP("gettextFromC", "Aug"), QT_TRANSLATE_NOOP("gettextFromC", "Sep"), QT_TRANSLATE_NOOP("gettextFromC", "Oct"), QT_TRANSLATE_NOOP("gettextFromC", "Nov"), QT_TRANSLATE_NOOP("gettextFromC", "Dec"),
+	};
+	return translate("gettextFromC", month_array[mon]);
+}