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

coition \coi"tion\, n. l. coitio, fr. coire to come together;
   co- + ire to go.
   a coming together; sexual intercourse; copulation. --grew.
   1913 webster

[2] : WordNet (r) 2.0

coition
     n : the act of sexual procreation between a man and a woman; the
         man's penis is inserted into the woman's vagina and
         excited until orgasm and ejaculation occur syn: sexual
         intercourse, intercourse, sex act, copulation, coitus,
          sexual congress, congress, sexual relation, relation,
          carnal knowledge
see also:
sexual intercourse intercourse sex act copulation coitus sexual congress 
congress sexual relation relation carnal knowledge 

Coition >> C Words
Coition, definition of term: Coition
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