from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun An advertisement.
  • noun An advantage in tennis.

from The Century Dictionary.

  • A prefix of Latin origin, with primary sense “to,” and hence also “toward, upon, for,” etc., expressing in Latin, and so in English, etc., motion or direction to, reduction or change into, addition, adherence, intensification, etc., in English often without perceptible force. According to the following consonant, it is variously assimilated ab-, ac-, af-, etc., or reduced to a-. See etymology.
  • A prefix of various other origin, erroneously put for other prefixes, as in advance, etc. See etymology.
  • A suffix in ballad and salad (formerly balade and salade), usually represented by -ade. See -ade.
  • A simplified spelling of add.
  • A suffix of Greek origin appended to nouns.
  • An abbreviation of advertisement.
  • In anatomy, a suffix denoting relation, situation, or direction, having the same force as the English suffix -ward, or the word toward.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • preposition to, toward
  • noun informal Short form of advertisement.
  • noun tennis advantage

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a public promotion of some product or service
  • adverb in the Christian era; used before dates after the supposed year Christ was born


from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin ad ("to, on").

from Wiktionary, Creative Commons Attribution/Share-Alike License

From a shortening of the word advertisement.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From a shortening of the word advantage.


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  • I think the folks at Eli Lilly missed a great opportunity for a slogan for their flagship ED drug: "For a good time, Cialis."

    October 24, 2007

  • Ha! You're right--that would have helped people remember how to pronounce that goofy name, also.

    November 16, 2007

  • An anonymous genius at my workplace used ad. as an abbreviation for adolescent. Very useful when the other category is adult.

    October 10, 2008

  • Auris dextra.

    February 18, 2009

  • L ad = 1. to (the point or pitch of), toward(s); 2. reaching to, up or down to, proceeding as far as, to the end of, up to; 3. including; 4. near, beside; 5. (presence) at; 6. at hand; 7. in (one’s ear); 8. in (the direction of); 9. in (time); in (the end); 8. into; 9. on (this side); 10. against; 11. throughout; 12. for; 13. outside of; 14. situated at; 15. off (shore); 16. in front of, before; 17. upwards; 18. in the eyes of; 19. approaching; 20. approximately; 21. in addition to, along with; 22. in preparation for, in expectation of; 23. until; 24. at the end of (a period); 25. after; 26. lastly.

    July 9, 2011