the words that appear on the Prince of Wales’s crest (= the design that represents his title). It was first used in 1346 and is German for ‘I serve’, indicating the Prince’s loyalty to the king or queen.
ICH DIEN
Meaning of ICH DIEN in English
Oxford guide to British and American culture English vocabulary. Руководство по британской и американской культуре, Оксфордский английский словарь. 2005