from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A polygon having seven sides.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A polygon with seven sides and seven angles.
from the GNU version of the Collaborative International Dictionary of English
- n. A plane figure consisting of seven sides and having seven angles.
from The Century Dictionary and Cyclopedia
- n. In geometry, a closed figure having seven angles successively united by lines.
- n. In fort, a place that has seven bastions for defense.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a seven-sided polygon
Latin heptagōnon, from Greek heptagōnos, having seven angles : hepta-, hepta- + -gōnos, angled; see -gon.(American Heritage® Dictionary of the English Language, Fourth Edition)
Since 16th century, from Ancient Greek ἑπτάγωνον (heptagonon), from ἑπτά (hepta, "seven") + γωνία (gonia, "angle"). (Wiktionary)