The word is only attested as a gloss to a passage in Alexander Nequam's Latin De Nominibus Utensilium which juxtaposes clangatores ('those who make noise, i.e. defy or provoke hostility') with caduciatores ('those who call for peace'). Different manuscripts seem to have confused the two terms, and the same Anglo-Norman gloss seems to be applied to both Latin words. As such, the word can be interpreted as an aphetic form of both afiur or defiur.