-ad


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-ad

suff.
In the direction of; toward: cephalad.

[From Latin ad, to; see ad- in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

-ad

suffix forming nouns
1. a group or unit (having so many parts or members): triad.
2. (Poetry) an epic poem concerning (the subject indicated by the stem): Dunciad.
[via Latin from Greek -ad- (plural -ades), originally forming adjectives; names of epic poems are all formed on the model of the Iliad]

-ad

suffix forming adverbs
(Anatomy) denoting direction towards a specified part in anatomical descriptions: cephalad.
[from Latin ad to, towards]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

ad1

(æd)

n.
1. an advertisement.
2. advertising: an ad agency.
[1835–45; by shortening]

ad2

(æd)

n. Tennis.
[1925–30; by shortening]

ad-

a prefix occurring in verbs or verbal derivatives borrowed from Latin, where it meant “toward” and indicated direction, tendency, or addition: adjoin. For variants before a following consonant, see a-5, ac-, af-, ag-, al-, an-2, ap-1, ar-, as-, at-.
[< Latin ad, ad- (preposition and prefix) to, toward, at, about; c. at1]

-ad1

,
1. a suffix occurring in loanwords from Greek denoting a group or unit comprising a certain number, sometimes of years: myriad; Olympiad; triad.
2. a suffix meaning “derived from,” “related to,” “associated with,” occurring in loanwords from Greek (dryad; oread) and in New Latin coinages on a Greek model (bromeliad; cycad).
3. a suffix used, on the model of Iliad, in the names of epics, speeches, etc., derived from proper names: Dunciad; jeremiad.
[< Greek -ad-, s. of -as]

-ad2

,
var. of -ade1: ballad; salad.

-ad3

,
a suffix used in anatomy to form adverbs from nouns signifying parts of the body, denoting a direction toward that part: ectad.
[< Latin ad toward, anomalously suffixed to the noun]

A.D.

or AD,

1. in the year of the Lord; since Christ was born: Charlemagne was born in a.d.742.
(Latin annō Dominī]
2. assembly district.
3. athletic director.
usage: The abbreviation a.d. was orig. placed before a date and is still usu. preferred in edited writing: The Roman conquest of Britain began in a.d.43 (or, sometimes, began a.d.43). The abbreviation b.c. (before Christ) is always placed after a date: Caesar was assassinated in 44 b.c. But by analogy with the position of b.c., a.d. is frequently found after the date in all types of writing: Claudius I lived from 10 b.c.to 54 a.d. This abbreviation may also designate centuries, being placed after the century specified: the second century a.d. Some writers prefer to use c.e. (Common Era) and b.c.e. (Before the Common Era) to avoid the religious overtones of a.d. and b.c.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.