mon·sei·gneur \|mänˌsān|yər(.)\noun (pluralmes·sei·gneurs \|māˌsān|yər(.), -rz\) Etymology: French, from Old French, literally, my lord : a French dignitary (as a prince or prelate) — used as a title of honor preceding a title of office or rank < Monseigneur the Archbishop > < Monseigneur the Dauphin > — abbr. Msgr.