Mon*sieur" (?), n.; pl. Messieurs (#). [F., fr. mon my + Sieur, abbrev. of seigneur lord. See Monseigneur.]
1.
The common title of civility in France in speaking to, or of, a man; Mr. or Sir.
[Represented by the abbreviation
M. or
Mons. in the singular, and by
MM.] or Messrs. in the plural.]
2.
The oldest brother of the king of France.
3.
A Frenchman.
[Contemptuous]
Shak.
© Webster 1913.