Heptagon
WordNet
noun
(1) A seven-sided polygon
WiktionaryText
Etymology
Since 16th century, from ἑπτάγωνον (heptagonon), from ἑπτά (hepta), seven, + γωνία (gonia), angle.
Since 16th century, from ἑπτάγωνον (heptagonon), from ἑπτά (hepta), seven, + γωνία (gonia), angle.