- before noon.
- the period from midnight to noon, especially the period of daylight prior to noon: Shall we meet Saturday a.m.?
- a morning newspaper, sometimes issued shortly before midnight.
- Master of Arts.
- Agricultural and Mechanical (college): Texas A and M.
abbreviation for (indicating the time period from midnight to midday)
- ante meridiemCompare p.m.
in hours, 1762, abbreviation of Latin ante meridiem “before noon.”
also AM, type of radio wave broadcast; see amplitude.