adversary, adversative, adversive, alien, antagonistic, anti, antipathetic, antithetic, antonymous, at cross-purposes, balancing, clashing, compensating, competitive, con, conflicting, confronting, contradictory, contradistinct, contrapositive, contrarious, contrary, contrasted, converse, counter, counteractive, counterbalancing, counterpoised, countervailing, cross, dead against, deleterious, detrimental, difficult, disaccordant, disadvantageous, discordant, discrepant, dissentient, enemy, eyeball to eyeball, fractious, hard, harmful, hostile, hurtful, impeding, in opposition, inconsistent, inimical, injurious, inverse, miserable, negative, noncooperative, not easy, obstinate, obstructive, obverse, opponent, opposed, opposing, opposite, oppositional, oppositive, oppugnant, overthwart, perverse, prejudicial, recalcitrant, refractory, repugnant, reverse, rigorous, rival, sinister, squared off, stressful, troublesome, troublous, trying, uncooperative, unfavorable, unfriendly, unpropitious, unsatisfactory, untoward, wretched