-hedral

-hedral

suff.
Having a specified kind or number of surfaces: dihedral.

[From -hedron.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

-hedron

a combining form used in the names of geometrical solid figures having the form or number of faces specified by the initial element: tetrahedron.
[< Greek -edron, neuter of -edros having bases, -sided, derivative of hédra seat, face of a geometrical form (compare cathedra)]
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