Alteration of -oma, from Ancient Greek -ωμα (-ōma).
Only partially cognate to -some (“body”), from σῶμα (sôma, “body”), in that both share the case ending -μα (-ma), but the ω is unrelated.
Back-formation from mitome, reinforced by chromosome. Early examples include biome (1916) and genome, from German Genom (1920). Some association with genetics due to occurrence in chromosome and genome.
Meanings
(morpheme) The complete whole of a class of substances for a species or an individual.