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definitions

-ad

1

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.

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Nearby words

  1. -aceae,
  2. -aceous,
  3. -acious,
  4. -acity,
  5. -acy,
  6. -ade,
  7. -adelphous,
  8. -ades,
  9. -ado,
  10. -ae

Origin of -ad

1
Greek -ad- (stem of -as), specialization of feminine adjective-forming suffix, often used substantively

-ad

2

variant of -ade1: ballad.

-ad

3

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

Origin of -ad

3
From the Latin word ad toward, anomalously suffixed to the noun; introduced as a suffix by Scottish anatomist John Barclay (1758–1826) in 1803
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for -ad

-ad

1

suffix forming nouns

a group or unit (having so many parts or members)triad
an epic poem concerning (the subject indicated by the stem)Dunciad

Word Origin for -ad

via Latin from Greek -ad- (plural -ades), originally forming adjectives; names of epic poems are all formed on the model of the Iliad

suffix forming adverbs

denoting direction towards a specified part in anatomical descriptionscephalad

Word Origin for -ad

from Latin ad to, towards
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
Word Origin and History for -ad

-ad

word-forming element denoting collective numerals (cf. Olympiad), plant families, and names of poems, from Greek -as (genitive -ados), a suffix forming fem. nouns; also used in fem. patronymics (Dryad, Naiad, also, in plural, Pleiades, Hyades).

Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for -ad

-ad

suff.

In the direction of; toward:cephalad.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.