icosagon

The story

1. Ancient Greek · derived fromεἰκοσάγωνος“having twenty sides”
2. English todayicosagon

From Ancient Greek εἰκοσάγωνος (eikoságōnos, “having twenty sides”), from εἴκοσι (eíkosi, “twenty”) + γωνία (gōnía, “angle”). Equivalent to icosa- + -gon.