harmful
[adjective]
Synonyms: destructive, damaging, deleterious, detrimental, hurtful, injurious, noxious, pernicious

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Antonyms: harmless
Contrasted words: innocuous, inoffensive, nontoxic, beneficent, beneficial, benign, benignant, favorable, helpful, salutary, useful, safe, unhazardous
Related Words: baleful, baneful, malefic, malign, malignant, noisome, noxious, pernicious, toxic, insalubrious, unhealthful, unhealthy, unwholesome, dangerous, hazardous, risky, unsafe

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English Thesaurus: harmful, be bad for somebody/something, damaging, detrimental, negative, ...

[TahlilGaran] English Synonym Dictionary ▲

harm‧ful /ˈhɑːmfəl $ ˈhɑːrm-/ adjective
[Word Family: noun: harm, harmlessness; adjective: unharmed, harmful ≠ harmless; verb: harm; adverb: harmlessly]
causing harm:
the harmful effects of smoking
harmful to
chemicals that are harmful to the environment

[TahlilGaran] Dictionary of Contemporary English ▲

harmful
adj.
VERBS be | become | consider sth She actually considered fresh air harmful.
ADV. extremely, particularly, positively, very These products are often positively harmful.
quite | possibly, potentially A lot of these chemicals are potentially very harmful.
allegedly | (not) necessarily Not all virus infections are necessarily harmful to vines.
intrinsically | environmentally, socially These pesticides are environmentally harmful.
PREP. to pesticides that are harmful to the environment

[TahlilGaran] Collocations Dictionary ▲

harmful causing physical harm – used especially about things that cause harm to your health, the environment etc:
Smoking is harmful to your health.
drugs with harmful side-effects
be bad for somebody/something to have a harmful effect on someone or something. This phrase is very commonly used in everyday English when saying that something is harmful:
Everyone knows that too much alcohol is bad for you.
damaging used about things that cause permanent physical harm, or that have a bad effect in other ways, for example on people’s opinion of someone:
Acid rain has a damaging effect on trees and the soil.
The allegations were very damaging to his career.
Constant criticism is damaging to a child’s self-esteem.
detrimental formal causing harm or having a bad effect on something:
Employers are worried that the new laws will have a detrimental effect on their business.
chemicals that are detrimental to the environment
policies that have been detrimental to the interests of old people
negative a negative effect is one that is bad and causes problems:
The car tax had a negative effect on car sales.
the negative impact of the recession in the US
hazardous hazardous substances are likely to be dangerous to people’s health and safety:
Hazardous waste needs to be disposed of safely.
hazardous chemicals
toxic toxic substances, smoke etc are poisonous:
toxic waste
toxic fumes
Toxic chemicals spilled into the river.
pernicious /pəˈnɪʃəs $ pər-/ formal used about something that has a gradual bad effect which is not easy to notice, especially on people’s morals, or on their health:
the pernicious effects of violent video games
the pernicious effect of secondhand smoke

[TahlilGaran] English Thesaurus ▲