diff --git a/libs/ardour/i18n.h b/libs/ardour/i18n.h
index dcbbfcf52e..43ae07cac1 100644
--- a/libs/ardour/i18n.h
+++ b/libs/ardour/i18n.h
@@ -12,5 +12,9 @@
 #define N_(Text) gettext_noop (Text)
 #define X_(Text) Text
 #define I18N(Array) PBD::internationalize (PACKAGE, Array)
+/** Use this to translate strings that have different meanings in different places.
+ *  Text should be of the form Context|Message.
+ */
+#define S_(Text) PBD::sgettext (PACKAGE, Text)
 
 #endif // __i18n_h__
diff --git a/libs/gtkmm2ext/i18n.h b/libs/gtkmm2ext/i18n.h
index 7c79d2eb53..edd0a9e315 100644
--- a/libs/gtkmm2ext/i18n.h
+++ b/libs/gtkmm2ext/i18n.h
@@ -7,5 +7,9 @@
 #define _(Text) dgettext (PACKAGE, Text)
 #define N_(Text) gettext_noop (Text)
 #define X_(Text) (Text)
+/** Use this to translate strings that have different meanings in different places.
+ *  Text should be of the form Context|Message.
+ */
+#define S_(Text) PBD::sgettext (PACKAGE, Text)
 
 #endif // __i18n_h__