Also found in: Thesaurus, Medical, Financial, Acronyms, Encyclopedia.
Related to ante meridiem: post meridiem
an·te me·rid·i·em(ăn′tē mə-rĭd′ē-əm)
adv. & adj. Abbr. AM or am or am
Before noon. Used chiefly in the abbreviated form to specify the hour: 10:30 am. See Usage Note at AM.
[Latin ante, before + merīdiem, accusative of merīdiēs, noon.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ante meridiem(ˈæntɪ məˈrɪdɪəm)
(Horology) the full form of a.m.
[Latin, from ante- + merīdiēs midday]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
am(æm; unstressed əm, m)
1st pers. sing. pres. indic. of be.
[before 900; Old English am, eam, eom]
1. Asian male.
2. amplitude modulation: a method of impressing a signal on a radio carrier wave by varying its amplitude.
3. a system of broadcasting using this method.Compare FM.
Master of Arts.
[< Latin Artium Magister]
1. before noon.
2. the period from midnight to noon, esp. the period of daylight prior to noon.Compare p.m.
[1755–65; < Latin ante merīdiem]
usage: The abbreviation a.m. 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 such as 6 a.m. in the morning and 9 p.m. at night are redundant.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
adv (abbr am) → vormittags
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007