Dictionary.com
Thesaurus.com
Synonyms

ad

1 American  
[ad] / æd /

noun

  1. advertisement.

  2. advertising.

    an ad agency.


-ad 2 American  
  1. a suffix occurring in loanwords from Greek denoting a group or unit comprising a certain number, sometimes of years: dyad; triad .

  2. 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 .


a.d. 3 American  
Or A.D.

abbreviation

  1. in the year of the Lord; since Christ was born.

    Charlemagne was born in a.d. 742.


ad 4 American  
[ad] / æd /

noun

Tennis.
  1. advantage.

  2. ad in, the advantage being scored by the server.

  3. ad out, the advantage being scored by the receiver.


-ad 5 American  
  1. variant of -ade: ballad .


a.d. 6 American  

abbreviation

  1. before the day.


ad 7 American  
[ad] / æd /

preposition

  1. (in prescriptions) to; up to.


-ad 8 American  
  1. Anatomy, Zoology. a suffix forming adverbs from nouns signifying parts of the body, denoting a direction toward that part: dextrad; dorsad; mediad .


a.d. 9 American  

abbreviation

  1. after date.

  2. autograph document.


ad- 10 American  
  1. a prefix occurring in loanwords from Latin, where it meant “toward” and indicated direction, tendency, or addition: adjoin . Usually assimilated to the following consonant; a-, ac-, af-, ag-, al-, an-, ap-, ar-, as-, at-.


ad. 11 American  

abbreviation

  1. adverb.

  2. advertisement.


A.D. 12 American  

abbreviation

  1. active duty.

  2. anno Domini. Also a.d.

  3. art director.

  4. assembly district.

  5. assistant director.

  6. athletic director.

  7. average deviation.


AD 1 British  

abbreviation

  1. anno Domini Compare BC

    70 ad

  2. military active duty

  3. military air defence

  4. Dame of the Order of Australia

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

-ad 2 British  

suffix

  1. a group or unit (having so many parts or members)

    triad

  2. an epic poem concerning (the subject indicated by the stem)

    Dunciad

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ad- 3 British  

prefix

  1. to; towards

    adsorb

    adverb

  2. near; next to

    adrenal

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

-ad 4 British  

suffix

  1. denoting direction towards a specified part in anatomical descriptions

    cephalad

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ad 5 British  
/ æd /

noun

  1. short for advertisement

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ad 6 British  
/ æd /

noun

  1. Brit equivalent: van.  short for advantage

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ad 7 British  

abbreviation

  1. Andorra

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

They took out an ad in the New York Times urging the impeachment of President Richard Nixon.

From The Wall Street Journal

The government estimates the ad ban will prevent around 20,000 cases of childhood obesity.

From BBC

Earlier this fall, she said, she called for the creation of an ad hoc committee that could serve as a bridge between the council and residents.

From Los Angeles Times

It also charges a fee when publishers use its ad network.

From The Wall Street Journal

He said Marie Curie first came to his attention when he saw an ad on TV.

From BBC