Harmful

a.

1.

Full of harm; injurious; hurtful; mischievous.

Adj.	1.	harmful - injurious to physical or mental health; "noxious chemical wastes"; "noxious ideas" Synonyms: noxious
	2.	harmful - able or likely to do harm
	3.	harmful - causing or capable of causing harm; "too much sun is harmful to the skin"; "harmful effects of smoking" Antonyms: harmless - not causing or capable of causing harm; "harmless bacteria"; "rendered the bomb harmless"
	4.	harmful - constituting a disadvantage Synonyms: disadvantageous
	5.	harmful - contrary to your interests or welfare; "adverse circumstances"; "made a place for themselves under the most untoward conditions" Synonyms: adverse, inauspicious, untoward
	6.	harmful - tending to cause great harm Synonyms: injurious, evil

adverse, antagonistic, bad, bad for, baleful, baneful, bitchy, conflicting, contaminated, contrary, corroding, corrosive, corrupting, corruptive, counter, counteractive, counterproductive, cussed, dangerous, deadly, deleterious, destructive, difficult, disadvantageous, disserviceable, distressing, evil, foul, hard, hateful, hazardous, hostile, hurtful, ill, in opposition, inimical, iniquitous, insalubrious, insanitary, invidious, lethal, malefic, maleficent, malevolent, malicious, malign, malignant, mean, 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