hendecagram

From hendeca- +‎ -gram.

 

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hendecagram

Wikipedia

hendecagram (plural hendecagrams)

1. A star polygon that has eleven vertices

• undecagram

• (star shape): pentagram (5-pointed), hexagram (6-pointed), heptagram (7-pointed), octagram (8-pointed), nonagram (9-pointed), decagram (10-pointed), hendecagram (11-pointed) dodecagram (12-pointed)