Undecagon n. : A figure having eleven angles and eleven sides.

Example:
How many interior angles does a Undecagon have?

Taxonomy
Hendecagon, Undecagon, free encyclopedia, sides, coinage, search, D11, edge length, sided polygon, side length, Indian, rupee, United States, geometry, dollar coin, perimeter, interactive animation, Personal tools.

Defination from the web:
Undecagon) Jump to: navigation, search. Regular hendecagon. Edges and vertices. 11. Schläfli symbols ... Properties of an Undecagon (hendecagon) With interactive animation. Weisstein, Eric W., "Hendecagon" from ...