(a) maybe not of the earth; preternatural; supernatural.
(a) Unnaturally odd and frightening. See Synonyms at unusual.
(a) Ridiculously unreasonable or uncustomary; absurd: called me personally at an unearthly hour.
maybe not earthly; maybe not terrestrial; supernatural; not like, or as if perhaps not proceeding from, anything belonging to the earth; unworldly; therefore, unusual; appalling: since, an unearthly weep or picture.