a.m. a.m. /ˌeɪ ˈɛm/

adjective

1. Before noon  ( a.m. , ante meridiem )
   before noon
   

 A.M.

adverb

1. "A.M." stands for "Ante Meridiem" in Latin, which translates to "before midday" in English. It is used to denote the hours of the day from midnight (12:00 A.M.) until just before noon (11:59 A.M.).  ( A.M. , ante meridiem )
   "A.M." stands for "Ante Meridiem" in Latin, which translates to "before midday" in English. It is used to denote the hours of the day from midnight (12:00 A.M.) until just before noon (11:59 A.M.).
    Let's meet at 11 A.M.
   let's meet at 11 A.M.