Phrase on a coat of arms (5)
I believe the answer is:
motto
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">phrase on a coat of arms</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for motto that I've seen before include "Maxim; slogan" , "Part of coat of arms" , "Catchphrase" , "Words often found on coat of arms" , "Christmas cracker text" .)