repellent

abominable disagreeable disgusting distasteful forbidding foul frigid frightful/frightening ghastly grungy gross hateful hideous horrible horrible/horrendous/horrid icky incommunicable indefinable inexpressible inhospitality inhospitableness insusceptible loathsome more horrible more horrible more horrid more frightening more horrendous most horrible most horrible most frightening most horrendous most horrid nasty obnoxious obscene objectionable odious offensive passionless repugnant repulsive resistant resistive revolting squalid ugly uncompassionate undesirable undescribable undesired ungraciousness unhospitable unpitying unreceptiveness unsavory unspeakable unstirred unsusceptible unsympathetic unutterable unwelcome unwelcomeness unwished-for vile vilest