Mon`sei`gneur" (?), n.; pl. Messeigneurs (#). [F., fr. mon my + seigneur lord, L. senior older. See Senior, and cf. Monsieur.]
My lord; -- a title in France of a person of high birth or rank; as, Monseigneur the Prince, or Monseigneur the Archibishop. It was given, specifically, to the dauphin, before the Revolution of 1789. (Abbrev. Mgr.)
© Webster 1913.