1informal A person who makes a mess, or who messes about; a muddler, a bungler.
2Irish, US A troublemaker, a thug.
Mid 17th century (in an earlier sense). From mess + -er.
A title of courtesy prefixed to the first name (sometimes with the surname also) of an Italian man (equivalent to the English Mr).
Mid 16th century; earliest use found in William Painter (?1540–1594), translator and administrator. From Italian messere, (before a title) messer, title of respect given to persons of importance, especially jurors, notaries, etc. from French mes sire.