undecagon

9.7

A flat shape with eleven straight sides and eleven angles

noun
/ˈʌndɪˌkæɡən/

Specialized

: undecágono

An undecagon has eleven sides.

Examples

To calculate the area of an undecagon, you need to know the length of its sides.
The ancient coin was shaped like an undecagon, making it unique among the other circular pieces.
In geometry class, we learned how to construct a regular undecagon using only a compass and straightedge.
The undecagon is a fascinating shape.
In geometry class, we learned how to construct a regular undecagon using only a compass and straightedge.
To calculate the area of an undecagon, you need to know the length of its sides.
The ancient coin was shaped like an undecagon, making it unique among the other circular pieces.

Synonyms

eleven-sided

vsundecagon

1 6.3

A flat shape with eleven straight sides

is the precise flat polygon with straight sides and eleven angles

Surface Forms

undecagon singular

undecagons plural

Morphology

undecagon = decagon (transparent) = un + decagon

The prefix 'un-' clearly indicates the addition of one more side to a decagon, forming an eleven-sided figure.

Etymology

Undecagon comes from the parts undeca- ('eleven') and -gon ('angle' or 'corner'), just like in hexagon or decagon. So an undecagon is a flat shape with eleven straight sides and eleven angles.