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.
My day began in the fitness center on Deck 16 at 7 a.m. and ended with a 7 p.m.
From The Wall Street Journal • Jun. 3, 2026
U.S. economic data due Monday include the S&P final U.S. manufacturing PMI for May at 9:45 a.m.
From MarketWatch • Jun. 1, 2026
He was thought to have been in the area of Angora Peak around 11 a.m., and the last anyone heard from him was around that afternoon, authorities said.
From Los Angeles Times • May 31, 2026
Huang’s presentation is slated to begin on Monday at 11 a.m.
From Barron's • May 29, 2026
At morning and evening worship, people drifted in and out, table manners were atrocious, one man took a walk into Haarlem every morning at 3:00 a.m.
From "The Hiding Place" by Corrie ten Boom
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.
