(American alsoA.M.) abbreviation
You use a.m. after a time to show that it is between midnight and midday: I start work at 9?a.m.
You use p.m. for times between midday and midnight.
a.m. BrE AmE (also am British English) /ˌeɪ ˈem/
[Date: 1700-1800; Language: Latin; Origin: ante meridiem 'before noon'] (ante meridiem) used to talk about times that are after ↑midnight but before ↑midday ⇨ p.m.:
Work starts at 9 am.
a.m.(NAmE alsoA.M.)[ˌeɪ ˈem][ˌeɪ ˈem]abbreviation
between midnight and midday (from Latin ‘ante meridiem ’) • It starts at 10 a.m. compare p.m. Word Origin:
a.m. (MORNING), am /ˌeɪˈem/
adverb
used when referring to a time between twelve o'clock at night and twelve o'clock in the middle of the day:
The first election results are expected around 1 a.m.