ante meridiem

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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]


(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.


Chem. Symbol.


1. America.
2. American.


Master of Arts.
[< Latin Artium Magister]


or A.M.,

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.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.ante meridiem - before noonante meridiem - before noon        
antemeridian - before noon
Adv.1.ante meridiem - before noonante meridiem - before noon; "let's meet at 11 A.M."
Latin - any dialect of the language of ancient Rome

ante meridiem

adv (abbr am) → vormittags
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References in periodicals archive ?
Ante meridiem is before midday; post meridiem is after midday, and midday itself cannot logically be classified as either after or before itself.
In order to induce liver injury in vivo using stepwise establishment, the rats both in the model control and treatment groups were intragastrically given 6g [kg.sup.-1] [d.sup.-1] (for a period of 1 week), 7 g [kg.sup.-1] [d.sup.-1] (for a period of 1 week), 8 g [kg.sup.-1] [d.sup.-1] (bra period of 1 week), and 9g [kg.sup.-1] [d.sup.-1] (fora period of 21 weeks) of distillate spirits (56% alcohol, v/v; Beijing Erguotou Wine Joint-Stock Limited Company, China) ante meridiem. At the same time, the rats in the treatment groups were intragastrically treated with silymarin (60 mg [kg.sup.-1] [d.sup.-1]) and PR (30, 60 and 120 mg [kg.sup.-1] [d.sup.-1]) post meridiem for a period of 24 weeks.
(ante meridiem!) when they get up in the morning, then after lunch at 2 p.m.