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inhuman vs. inhumane

inhuman

[in-hyoo-muhn, -yoo-] / ɪnˈhju mən, -ˈju- /

adjective

lacking qualities of sympathy, pity, warmth, compassion, or the like; cruel; brutal.

an inhuman master.

Synonyms:

brutish, savage, hard, callous, cold, unsympathetic, unfeeling
not suited for human beings.
not human.

inhumane

[in-hyoo-meyn, -yoo-] / ˌɪn hjuˈmeɪn, -ju- /

adjective

not humane; lacking humanity, kindness, compassion, etc.