ad
1 American-
a suffix occurring in loanwords from Greek denoting a group or unit comprising a certain number, sometimes of years: dyad; triad .
-
a suffix meaning “derived from,” “related to,” “concerned with,” “associated with” (oread ), introduced in loanwords from Greek (Olympiad; oread ), used sporadically in imitation of Greek models, as Dunciad , after Iliad .
abbreviation
noun
-
ad in, the advantage being scored by the server.
-
ad out, the advantage being scored by the receiver.
abbreviation
preposition
abbreviation
-
after date.
-
autograph document.
abbreviation
-
adverb.
-
advertisement.
abbreviation
-
anno Domini Compare BC
70 ad
-
military active duty
-
military air defence
-
Dame of the Order of Australia
suffix
-
a group or unit (having so many parts or members)
triad
-
an epic poem concerning (the subject indicated by the stem)
Dunciad
prefix
-
to; towards
adsorb
adverb
-
near; next to
adrenal
suffix
noun
noun
abbreviation
Usage
Because anno Domini means “in the year of the Lord,” its abbreviation a.d. was originally placed before rather than after a date: The Roman conquest of Britain began in a.d. 43 (or began a.d. 43). In edited writing, it is still usually placed before the date. But, by analogy with the position of b.c. “before Christ,” which always appears after a date ( Caesar was assassinated in 44 b.c. ), a.d. is also frequently found after the date in all types of writing, including historical works: The Roman emperor Claudius I lived from 10 b.c. to 54 a.d. Despite its literal meaning, a.d. is also used to designate centuries, being placed after the specified century: the second century a.d.
In strict usage, ad is only employed with specific years: he died in 1621 ad , but he died in the 17th century (and not the 17th century ad ). Formerly the practice was to write ad preceding the date ( ad 1621 ), and it is also strictly correct to omit in when ad is used, since this is already contained in the meaning of the Latin anno Domini (in the year of Our Lord), but this is no longer general practice. bc is used with both specific dates and indications of the period: Heraclitus was born about 540 bc ; the battle took place in the 4th century bc
Etymology
Origin of ad1
First recorded in 1795–1800; by shortening
Origin of -ad2
Greek -ad- (stem of -as ), specialization of feminine adjective-forming suffix, often used substantively
Origin of a.d.3
From Latin annō Dominī
Origin of ad4
First recorded in 1915–20; by shortening
Origin of a.d.6
From Latin ante diem
Origin of ad7
From Latin
Origin of -ad8
From the Latin word ad toward, anomalously suffixed to the noun; introduced as a suffix by Scottish anatomist John Barclay (1758–1826) in 1803
Origin of ad-10
< Latin ad, ad- (preposition and prefix) to, toward, at, about; cognate with at 1
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
While this ad hoc adjustment will probably make the authors cringe, the results show that the share of Social Security income remaining after out-of-pocket medical spending is 71% for the median beneficiary.
From MarketWatch
In the past, insurers have deployed phalanxes of angry seniors and run large-scale ad campaigns, including a commercial during the Super Bowl.
Since last summer, FAT Brands has been in talks with an ad hoc group of lenders to restructure its debt of some $1.4 billion out of court, a sum primarily held in special purpose vehicles.
It’s a link at the top of the screen, with a box around the word “ad.”
From Literature
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Advertising revenue remains the engine funding this buildout, which makes any weakening in ad pricing or engagement a structural problem, not just a cyclical one.
From MarketWatch
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.