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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.]
ante meridiem(ˈæntɪ məˈrɪdɪəm)
(Horology) the full form of a.m.
[Latin, from ante- + merīdiēs midday]
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.
adv (abbr am) → vormittags