n. [ Pref. deca- + Gr. &unr_; a corner or angle: cf. F. décagone. ] (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 ]
a. Pertaining to a decagon; having ten sides.
n. [ Gr. &unr_; twelve + &unr_; angle: cf. F. dodécagone. ] (Geom.) A figure or polygon bounded by twelve sides and containing twelve angles. [ 1913 Webster ]
n. [ See Hendecagon. ] (Geom.) A plane figure of eleven sides and angles. [ 1913 Webster ]
n. [ Gr. &unr_; eleven + &unr_; angle: cf. F. hendécagone. ] (Geom.) A plane figure of eleven sides and eleven angles.
n. [ L. quindecim fifteen + Gr. &unr_; angle. ] (Geom.) A plane figure with fifteen angles, and consequently fifteen sides. [ 1913 Webster ]
n. [ L. undecim eleven + Gr. &unr_; an angle. ] (Geom.) A figure having eleven angles and eleven sides. [ 1913 Webster ]