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

hexagram \hex"agram\, n. hexa- + -gram.
   a figure of six lines; specif.:
   a a figure composed of two equal triangles intersecting so
       that each side of one triangle is parallel to a side of
       the other, and the six points coincide with those of a
       hexagon.
   b in chinese literature, one of the sixty-four figures
       formed of six parallel lines continuous or broken,
       forming the basis of the i ching yih king, or "book of
       changes." --s. w. williams.
       webster 1913 suppl.

[2] : WordNet (r) 2.0

hexagram
     n : a regular polygon formed by extending each of the sides of a
         regular hexagon to form two equilateral triangles

Hexagram >> H Words
Hexagram, definition of term: Hexagram
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