toxic
[adjective]
Synonyms: poisonous, deadly, harmful, lethal, noxious, pernicious, pestilential, septic

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Antonyms: nontoxic

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

[TahlilGaran] English Synonym Dictionary ▲

tox‧ic /ˈtɒksɪk $ ˈtɑːk-/ adjective
[Date: 1600-1700; Language: Late Latin; Origin: toxicus, from Latin toxicum 'poison', from Greek toxikon 'arrow poison', from toxon 'bow, arrow']
containing poison, or caused by poisonous substances ⇒ toxin:
fumes from a toxic waste dump
toxic chemicals/substances/fumes/gases
Toxic chemicals were spilled into the river.
a highly toxic pesticide
—toxicity /tɒkˈsɪsəti, tɒkˈsɪsɪti $ tɑːk-/ noun [uncountable and countable]:
The metal has a relatively low toxicity to humans.

[TahlilGaran] Dictionary of Contemporary English ▲

toxic
adj.
VERBS be, stay | become | remain
ADV. extremely, highly, very | quite | potentially potentially toxic chemicals
PREP. to This chemical is toxic to many forms of life.

[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 ▲

poisonous containing or producing a substance that is likely to kill you, or make you very ill:
poisonous gas
poisonous snakes
The plant is poisonous to humans and animals.
toxic toxic chemicals and waste are poisonous to people and the environment:
Crops were sprayed with highly toxic chemicals.
Lead is toxic to humans.
The site was used for the disposal of toxic waste.
noxious [usually before noun] formal noxious substances and gases are poisonous:
Vehicles pollute the air with noxious fumes
The soil may be contaminated with noxious substances.
hazardous [usually before noun] hazardous substances are likely to harm people, animals, or the environment if they are not dealt with or got rid of carefully:
Lead is one of the most hazardous substances known, causing cancer and nerve damage.
The building is now unoccupied, and all radioactive or hazardous materials have been removed.
hazardous nuclear waste
deadly extremely poisonous and likely to kill you – used especially about poisons and snakes:
a deadly poison
a deadly snake
Terrorists plotted to release a deadly gas.

[TahlilGaran] English Thesaurus ▲