diff --git a/po/pl.po b/po/pl.po
index 13fc7d3a2..adb60efa8 100644
--- a/po/pl.po
+++ b/po/pl.po
@@ -1303,7 +1303,7 @@ msgstr "Listopad"
 
 #: js/messages.php:150
 msgid "December"
-msgstr ""
+msgstr "Grudzień"
 
 #. l10n: Short month name
 #: js/messages.php:154 libraries/common.lib.php:1566