'Decagon' definitions:
Definition of 'decagon'
From: WordNet
noun
A polygon with 10 sides and 10 angles
Definition of 'Decagon'
From: GCIDE
- Decagon \Dec"a*gon\, n. [Pref. deca- + Gr. ? a corner or angle: cf. F. d['e]cagone.] (Geom.) A plane figure having ten sides and ten angles; any figure having ten angles. A regular decagon is one that has all its sides and angles equal. [1913 Webster]