(a.) Full of harm; injurious; hurtful; mischievous.

adverse antagonistic bad bad for baleful baneful bitchy conflicting contaminated contrary corroding corrosive corrupting corruptive counter counteractive counterproductive cussed damaging dangerous deadly deleterious destructive detrimental difficult disadvantageous disserviceable distressing evil foul hard hateful hazardous hostile hurtful ill in opposition inimical iniquitous injurious insalubrious insanitary invidious lethal malefic maleficent malevolent malicious malign malignant mean mischievous miserable morbific nasty noisome not easy noxious ominous opposed opposing opposite ornery pathogenic peccant pernicious pestiferous poisonous polluted prejudicial rigorous risky scatheful septic sinister stressful tainted toxic troublesome troublous trying unadvantageous unfavorable unhealthful unhealthy unhygienic unprofitable unrewarding unsafe unsanitary untoward unwholesome useless venenate veneniferous venenous venomous vicious virulent wicked worthless wretched