n. pl. Mes·sieurs (mā-syœ, mĕsərz)
1. Abbr. M Used as a courtesy title before the surname, full name, or professional title of a man in a French-speaking area: Monsieur Cartier; Monsieur Jacques Cartier.
2. monsieur Used as a form of polite address for a man in a French-speaking area.
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