Mes·sei·gneurs (mā-sě-nyɶr') n. Plural of Monseigneur.
Mon·sei·gneur (môɴ-sě-nyɶr') n.
pl.Mes·sei·gneurs (mā-sě-nyɶr') Abbr. Msgr. or Mgr. Used as an honorific in French-speaking areas, especially as accorded to princes and prelates.
[French, from Old French seignor : mon, my; see Monsieur + seigneur, lord, sir; see seignior.]
1610, from Fr., title of honor equivalent to "my lord," from mon "my" + seigneur "lord," from L. seniorem, acc. of senior "older." Plural messeigneurs.