1) Figure with 1440 degrees 2) It has 10 angles 3) Plane figure with 10 sides 4) Polygon 5) Polygonal shape 6) Shape of some foreign coins 7) Ten-sided figure 8) Ten-sided shape 
In geometry, a decagon is any polygon with ten sides and ten angles. A regular decagon has all sides of equal length and each internal angle equal to 144°. Its Schläfli symbol is {10}. ===Construction=== A regular decagon is constructible using compass and straightedge: An alternative (but similar) method is as follows: ==Related figures== There...
• (n.) 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.
A polygon with 10 sides. Each interior angle of a regular decagon is 144°.
Dec'a·gon noun [ Prefix deca- + Greek ... a corner or angle: confer French 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. 
A decagon is a ten-sided polygon.
[n] - a polygon with 10 sides and 10 angles
A ten sided polygon.
A polygon with ten sides. Each internal angle is 144° and the sum of the internal angles is 1440°. See also: Polygon, Regular Polygon.
noun a polygon with 10 sides and 10 angles
In geometry, a ten-sided polygon
a polygon having ten angles and ten sides.
A polygon/shape with ten angles and ten straight lines.