Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary
1

ad

play
noun, often attributive \ˈad\

Definition of ad



1841

First Known Use of ad

1841


2

ad

noun

Definition of ad

  1. :  advantage 4



Circa 1928

First Known Use of ad

circa 1928

Rhymes with ad


AD

abbreviation

Definition of AD

  1. 1 active duty

  2. 2 after date

  3. 3 Alzheimer's disease

  4. 4 anno Domini —often printed in small capitals and often punctuated

  5. 5 assembly district

  6. 6 assistant director

  7. 7 athletic director




ad-

prefix

Definition of ad-

  1. 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. 2 :  near :  adjacent to —in this sense always in the form ad- <adrenal>



Variants of ad-

or

ac-

or

af-

or

ag-

or

al-

or

ap-

or

as-

or

at-

Origin and Etymology of ad-

Middle English, from Anglo-French & Latin; Anglo-French, from Latin, from ad — more at at


1

-ad

adverb suffix

Definition of -ad

  1. :  in the direction of :  toward <cephalad>



Origin and Etymology of -ad

Latin ad


2

-ad

noun suffix

Definition of -ad

  1. :  member of a botanical group <bromeliad>



Origin and Etymology of -ad

probably from New Latin -ad-, -as, from Greek, suffix denoting descent from or connection with



AD Defined for Kids

ad

play
noun \ˈad\

Definition of ad for Students




Medical Dictionary

AD

abbreviation

Medical Definition of AD

  1. 1Alzheimer disease; Alzheimer's disease

  2. 2atopic dermatitis

  3. 3[Latin auris dextra] right ear—used especially in audiology and in writing medical prescriptions

  4. 4average deviation




Learn More about ad


Seen and Heard

What made you want to look up ad? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

a simplified speech bridging languages

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

confounded-person

Which is a synonym of indolent?

philistine melancholy lazy frenetic
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ