a combining form meaning “other,” used in the formation of compound words (allotrope) and in chemistry to denote the more stable of two geometric isomers.
Also (except in chemistry), especially before a vowel, all-.
Origin
< Greek, combining form of állos other; cognate with Latinalius,else
British Dictionary definitions for allo-
allo-
combining form
1.
indicating difference, variation, or opposition: allopathy, allomorph, allophone, allonym
Word Origin
from Greek allos other, different
Word Origin and History for allo-
word-forming element meaning "other," from Greek allo-, comb. form of allos "other, different" (see alias (adv.)).