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

familiarity \famil`iar"ity\, n.; pl. familiarities. oe.
   familarite, f. familiarit'efr. l. faniliaritas. see
   familiar.
   1. the state of being familiar; intimate and frequent
      converse, or association; unconstrained intercourse;
      freedom from ceremony and constraint; intimacy; as, to
      live in remarkable familiarity.
      1913 webster

   2. anything said or done by one person to another
      unceremoniously and without constraint; esp., in the pl.,
      such actions and words as propriety and courtesy do not
      warrant; liberties.

   syn: acquaintance; fellowship; affability; intimacy. see
        acquaintance.
        1913 webster
see also:
familiarities familiar acquaintance 

[2] : WordNet (r) 2.0

familiarity
     n 1: personal knowledge or information about someone or something
          syn: acquaintance, conversance, conversancy
     2: usualness by virtue of being familiar or well known ant: unfamiliarity
     3: close or warm friendship; "the absence of fences created a
        mysterious intimacy in which no one knew privacy" syn: intimacy,
         closeness
     4: a casual manner syn: casualness
     5: an act of undue intimacy syn: impropriety, indecorum, liberty
see also:
acquaintance conversance conversancy unfamiliarity intimacy closeness 
casualness impropriety indecorum liberty 

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

104 moby thesaurus words for "familiarity":
   bohemianism, acquaintance, affability, affinity, amiability,
   assumption, awareness, boldness, casualness, chumminess, civility,
   closeness, clubbability, clubbishness, clubbism, cognition,
   cognizance, common touch, communicativeness, companionability,
   compatibility, comprehension, congeniality, cordiality, corpus,
   courtesy, data, datum, ease, easiness, easygoingness, experience,
   expertise, facts, factual base, fellowship, folksiness,
   fondness for society, friendliness, geniality, graciousness, grasp,
   gregariousness, homeliness, homeyness, hospitality, hubris,
   impertinence, imposition, impropriety, impudence, informality,
   informalness, information, inseparableness, insolence,
   intelligence, intimacy, intimate acquaintance, inwardness,
   irregularity, ken, know-how, knowing, knowledge, lawlessness,
   liberties, liberty abused, license, licentiousness, looseness,
   mateyness, naturalness, nearness, offhandedness, openness,
   palliness, plainness, practical knowledge, presumption,
   presumptuousness, private knowledge, privity, ratio cognoscendi,
   relaxedness, self-knowledge, simplicity, sociability, sociableness,
   social grace, sociality, special affinity, technic, technics,
   technique, unaffectedness, unceremoniousness, unconstrainedness,
   unconstraint, unconventionality, understanding, undue liberty,
   unpretentiousness, urbanity

Familiarity >> F Words
Familiarity, definition of term: Familiarity
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