from The American Heritage® Dictionary of the English Language, 4th Edition
- suffix A crystal or geometric figure having a specified kind or number of surfaces: heptahedron.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- suffix Used in geometry to form the names of solid figures bounded by a certain number of planes (polyhedra).
New Latin, from Greek -edron, neuter of -edros, -sided, from hedrā, face; see sed- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek ἕδρα (hedra, "face of a geometrical solid") (Wiktionary)