diff --git a/install/lang/el/langconfig.php b/install/lang/el/langconfig.php
index 6e1a88945a1..6fc9dec8321 100644
--- a/install/lang/el/langconfig.php
+++ b/install/lang/el/langconfig.php
@@ -30,5 +30,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
+$string['parentlanguage'] = '';
 $string['thisdirection'] = 'ltr';
 $string['thislanguage'] = 'Ελληνικά';