ad

1 of 7

noun (1)

often attributive
1
: advertisement sense 1
newspapers ads
TV ads for new cars
2
: advertising
an ad agency

ad

2 of 7

noun (2)

AD

3 of 7

abbreviation (1)

1
active duty
2
after date
3
4
Alzheimer's disease
5
anno Domini
often printed in small capitals and often punctuated
6
assembly district
7
assistant director
8
athletic director
9
right ear
used especially in audiology and in writing medical prescriptions

A/D

4 of 7

abbreviation (2)

analog/digital

ad-

5 of 7

prefix

variants or ac- or af- or ag- or al- or ap- or as- or at-
1
: to : toward
usually ac- before c, k, or q
acculturation
and af- before f
affluent
and ag- before g
aggradation
and al- before l
alliteration
and ap- before p
apportion
and as- before s
assuasive
and at- before t
attune
and ad- before other sounds but sometimes ad- even before one of the listed consonants
adsorb
2
: near : adjacent to
in this sense always in the form ad-
adrenal

-ad

6 of 7

adverb suffix

: in the direction of : toward
cephalad

-ad

7 of 7

noun suffix

: member of a botanical group
bromeliad

Word History

Etymology

Noun (1)

by shortening

Noun (2)

by shortening

Prefix

borrowed from Latin, prefix forming verbs and verbal derivatives, marking movement toward, tendency, addition, from ad, preposition, "to, as far as, at, near, in accordance with" — more at at entry 1

Adverb suffix

borrowed from Latin ad "to, toward" — more at at entry 1

Noun suffix

borrowed from New Latin -ad-, -as, borrowed from Greek -ad-, -as, feminine noun suffix denoting descent from or connection with

First Known Use

Noun (1)

1799, in the meaning defined at sense 1

Noun (2)

1915, in the meaning defined above

Time Traveler
The first known use of ad was in 1799

Dictionary Entries Near ad

Cite this Entry

“Ad.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ad. Accessed 26 Nov. 2022.

Kids Definition

ad 1 of 2

noun

ˈad

ad-

2 of 2

prefix

variants or ac- or af- or ag- or al- or ap- or as- or at-
: to : toward
usually ac- before c, k, or q and af- before f and ag- before g and al- before l and ap- before p and as- before s and at- before t and ad- before other sounds but sometimes ad- even before one of the listed consonants

Medical Definition

1
2
3
[Latin auris dextra] right ear
used especially in audiology and in writing medical prescriptions
4
average deviation

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