[ped-ee-uh n, pee-dee-]
noun, plural ped·i·a [ped-ee-uh, pee-dee-uh] /ˈpɛd i ə, ˈpi di ə/. Crystallography.
a crystal form having only a single face, without a symmetrical equivalent: unique to the triclinic system.
Origin of pedion
1885–90; < New Latin < Greek pedíon plain, level ground, diminutive of pédon ground, earth
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019