Electronics. amplitude modulation: a method of impressing a signal on a radio carrier wave by varying its amplitude.
Radio. a system of broadcasting by means of amplitude modulation.
of, relating to, or utilizing such a system.
Asian male.
America.
American.
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.
associate member
Assembly Member (of the National Assembly of Wales)
Albert Medal
Master of Arts
Also: am. amplitude modulation
See a.m.
Member of the Order of Australia
Armenia (international car registration)
The abbreviation a.m. for Latin ante merīdiem, meaning “before noon,” refers to the period from midnight until noon. One minute before noon is 11:59 a.m. One minute after noon is 12:01 p.m. Many people distinguish between noon and midnight by saying 12 noon and 12 midnight. Expressions combining a.m. with morning ( 6 a.m. in the morning ) and p.m. with afternoon, evening, or night ( 9 p.m. at night ) are redundant and occur most often in casual speech and writing. Both a.m. and p.m. sometimes appear in capital letters, especially in printed matter.
First recorded before 900; Middle English; Old English am, eam, eom; cognate with Gothic im, Old Norse, Armenian em, Old Irish am (from unattested esmi ), Attic Greek eimí, Aeolic Greek émmi, Doric Greek ēmí (all from prehistoric Greek esmi ), Hittite esmi, early Lithuanian esmì, Old Church Slavonic yesmĭ, Albanian jam (from unattested esmi ), Sanskrit ásmi, from unattested Proto-Indo-European ésmi, from root es- “to be” + -m 1st person singular + -i, present-time marker; cf. is
First recorded in 1935–40
From Latin ante merīdiem
A.M. ( def. 2 ) from Latin Artium Magister
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
A November report from insurance ratings firm AM Best showed Gen Re’s premiums written and financial cushion had both grown over the previous five years.
From The Wall Street Journal • May 28, 2026
His favorite is 1984’s jazzy “2:00 AM Paradise Cafe,” on which he collaborated with Mulligan, Sarah Vaughan and Mel Tormé.
From Los Angeles Times • May 27, 2026
In 2025, they reported $413 billion worth, according to insurance ratings firm AM Best, twice as much as in 2020.
From The Wall Street Journal • May 26, 2026
"Soccer AM opened it up to every other fan out there. You would have them all speaking about the Showboat. It was nice to be in with some world-class players."
From BBC • Mar. 24, 2026
She’d noted it in the corner with what appeared to be a matrix of some sort: GB AM 222 I was trying to figure out what it meant, when hinges squeaked.
From "Burning Blue" by Paul Griffin
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
