[1] : The Collaborative International Dictionary of English v.0.48

acquaintance \acquaint"ance\, n. oe. aqueintance, of.
   acointance, fr. acointier. see acquaint.
   1. a state of being acquainted, or of having intimate, or
      more than slight or superficial, knowledge; personal
      knowledge gained by intercourse short of that of
      friendship or intimacy; as, i know the man; but have no
      acquaintance with him.
      1913 webster

            contract no friendship, or even acquaintance, with a
            guileful man.                         --sir w.
                                                  jones.
      1913 webster

   2. a person or persons with whom one is acquainted.
      1913 webster

            montgomery was an old acquaintance of ferguson.
                                                  --macaulay.
      1913 webster

   note: in this sense the collective term acquaintance was
         formerly both singular and plural, but it is now
         commonly singular, and has the regular plural
         acquaintances.
         1913 webster

   to be of acquaintance, to be intimate.

   to take acquaintance of or with, to make the acquaintance
      of. obs.
      1913 webster

   syn: familiarity; intimacy; fellowship; knowledge.

   usage: acquaintance, familiarity, intimacy. these words
          mark different degrees of closeness in social
          intercourse. acquaintance arises from occasional
          intercourse; as, our acquaintance has been a brief
          one. we can speak of a slight or an intimate
          acquaintance. familiarity is the result of continued
          acquaintance. it springs from persons being frequently
          together, so as to wear off all restraint and reserve;
          as, the familiarity of old companions. intimacy is the
          result of close connection, and the freest interchange
          of thought; as, the intimacy of established
          friendship.
          1913 webster

                our admiration of a famous man lessens upon our
                nearer acquaintance with him.     --addison.
          1913 webster

                we contract at last such a familiarity with them
                as makes it difficult and irksome for us to call
                off our minds.                    --atterbury.
          1913 webster

                it is in our power to confine our friendships
                and intimacies to men of virtue.  --rogers.
          1913 webster
see also:
acquaint to be of acquaintance to take acquaintance of with acquaintance familiarity 
intimacy 

[2] : WordNet (r) 2.0

acquaintance
     n 1: personal knowledge or information about someone or something
          syn: familiarity, conversance, conversancy
     2: a relationship less intimate than friendship syn: acquaintanceship
     3: a person with whom you are acquainted; "i have trouble
        remembering the names of all my acquaintances"; "we are
        friends of the family" syn: friend
see also:
familiarity conversance conversancy acquaintanceship friend 

[3] : Moby Thesaurus II by Grady Ward, 1.0

111 moby thesaurus words for "acquaintance":
   account, acquaintedness, advocate, alter ego, amigo, announcement,
   appreciation, apprehension, associate, awareness, backer,
   best friend, blue book, bosom friend, briefing, brother, bulletin,
   casual acquaintance, close acquaintance, close friend, colleague,
   communication, communique, companion, comrade, confidant,
   confidante, consciousness, corpus, crony, data, datum, directory,
   dispatch, enlightenment, evidence, experience, expertise, facts,
   factual base, factual information, familiar, familiarity,
   familiarization, favorer, fellow, fellow creature, fellowman,
   friend, gen, general information, grasp, guidebook, handout,
   hard information, incidental information, info, information,
   inseparable friend, instruction, intelligence, intimacy, intimate,
   introduction, inwardness, ken, knockdown, know-how, knowing,
   knowledge, light, lover, mate, mention, message, neighbor, notice,
   notification, other self, partisan, pickup, practical knowledge,
   presentation, private knowledge, privity, promotional material,
   proof, publication, publicity, ratio cognoscendi, release, report,
   repository, self-knowledge, sidelight, statement, supporter,
   sympathizer, technic, technics, technique, the dope, the goods,
   the know, the scoop, transmission, understanding, well-wisher,
   white book, white paper, word

[4] : THE DEVIL'S DICTIONARY ((C)1911 Released April 15 1993)

acquaintance, n.  a person whom we know well enough to borrow from,
but not well enough to lend to.  a degree of friendship called slight
when its object is poor or obscure, and intimate when he is rich or
famous.

Acquaintance >> A Words
Acquaintance, definition of term: Acquaintance
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