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

tetragon \tet"ragon\, n. l. tetragonum, gr. tetra`gwnon;
   te`tra- see tetra- + gwni`a corner, angle: cf. f.
   t'etragone.
   1. geom. a plane figure having four sides and angles; a
      quadrangle, as a square, a rhombus, etc.
      1913 webster

   2. astrol. an aspect of two planets with regard to the
      earth when they are distant from each other ninety
      degrees, or the fourth of a circle. --hutton.
      1913 webster
see also:
tetra- 

[2] : WordNet (r) 2.0

tetragon
     n : a four-sided polygon syn: quadrilateral, quadrangle
see also:
quadrilateral quadrangle 

Tetragon >> T Words
Tetragon, definition of term: Tetragon
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