(a.) Attended with disadvantage; unfavorable to success or prosperity; inconvenient; prejudicial; -- opposed to advantageous; as, the situation of an army is disadvantageous for attack or defense.

baleful baneful corroding corrosive corrupting corruptive counterproductive damaging deadly deleterious depreciative depreciatory detracting detrimental disparaging disserviceable distressing harmful hurtful injurious lethal malefic malevolent malign malignant mischievous noisome noxious ominous pejorative pernicious poisonous prejudicial scatheful slighting toxic unadvantageous uncomplimentary unfavorable unprofitable unrewarding useless venenate veneniferous venenous venomous vicious virulent worthless