a.m. (ante meridiem)

Definition:
The abbreviation a.m. stands for ante meridiem, a Latin phrase meaning “before midday.” It is used to show times between midnight (12:00 a.m.) and just before noon (11:59 a.m.) on a 12-hour clock.

Example:

• 7:30 a.m. means half past seven in the morning.
• School might start at 9:00 a.m.

Tip:
Think of a.m. as “at morning” to help remember that it covers the morning hours.