|a.||1.||Full of harm; injurious; hurtful; mischievous.|
|Adj.||1.||harmful - injurious to physical or mental health; "noxious chemical wastes"; "noxious ideas"|
|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"|
harmless - not causing or capable of causing harm; "harmless bacteria"; "rendered the bomb harmless"
|4.||harmful - constituting a disadvantage|
|5.||harmful - contrary to your interests or welfare; "adverse circumstances"; "made a place for themselves under the most untoward conditions"|
|6.||harmful - tending to cause great harm|