diff --git a/po/pl.po b/po/pl.po
index 3ce3a945f..a147667b5 100644
--- a/po/pl.po
+++ b/po/pl.po
@@ -1389,7 +1389,7 @@ msgstr "Środa"
 
 #: js/messages.php:183
 msgid "Thursday"
-msgstr ""
+msgstr "Czwartek"
 
 #: js/messages.php:184
 #, fuzzy