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

quadrennial \quadren"nial\, a. l. quadriennium a space of
   four years; quattuor four + annus year; cf. l. quadriennis.
   see quadrate, and annual.
   1. comprising four years; as, a quadrennial period.
      1913 webster

   2. occurring once in four years, or at the end of every four
      years; as, quadrennial games.
      1913 webster
see also:
quadrate annual 

Quadrennial >> Q Words
Quadrennial, definition of term: Quadrennial
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