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Dangerous or harmful - thesaurus

Synonyms

dangerous

adjective

likely to harm or kill someone, or to damage or destroy something

harmful

adjective

causing harm

disastrous

adjective

causing a lot of damage or harm

damaging

adjective

causing physical harm to something so that it is broken, spoiled, or injured

risky

adjective

involving the possibility of danger, harm, or failure

hazardous

adjective

dangerous, especially to people’s health or safety

unsafe

adjective

dangerous

ruinous

adjective

causing severe damage or loss

perilous

adjective

mainly literary very dangerous

injurious

adjective

formal causing harm or damage

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More synonyms

adverse

adjective

negative, unpleasant, or harmful

at your peril

mainly literary used for saying that doing something is dangerous or could cause serious problems

calamitous

adjective

formal causing serious damage, or causing a lot of people to suffer

cataclysmic

adjective

changing a situation in a sudden, violent, and unpleasant way

catastrophic

adjective

causing a lot of damage, or making a lot of people suffer

combustible

adjective

likely to suddenly become dangerous or violent

convulsive

adjective

mainly journalism causing major problems or serious harm

damaging

adjective

having a negative effect on someone or something

dangerous

adjective

likely to have a bad effect or to cause a problem

dangerously

adverb

to such a degree that harm, death, damage, or destruction is possible

dangerously

adverb

in a way that is likely to harm someone or to damage something

dark

adjective

morally bad, dangerous, or frightening

deadly

adjective

able or likely to kill people

deleterious

adjective

very formal harmful

destructive

adjective

causing severe damage or harm

detrimental

adjective

harmful or damaging

devastating

adjective

causing a lot of harm or damage

dicey

adjective

informal involving danger or risk

dodgy

adjective

Britishinformal dangerous or not certain

dubious

adjective

not completely good, safe, or honest

explosive

adjective

likely to create difficulties or to have a dangerous or violent effect

fatal

adjective

causing someone to die

ferocious

adjective

violent and able to cause serious damage or injury

hairy

adjective

informal frightening, or dangerous

hostile

adjective

a hostile place or situation is difficult or dangerous to be in

hot

adjective

difficult, or dangerous

ill

adjective

bad, or harmful

inimical

adjective

formal causing harm, or stopping the development of something

insidious

adjective

something that is insidious is dangerous because it seems to be harmless or not important but in fact causes harm or damage

kamikaze

adjective

a kamikaze action is dangerous and likely to kill or harm the person doing it

lethal

adjective

very dangerous and able to kill you

lunatic

adjective

extreme, or dangerous

malign

adjective

literary causing harm

marauding

adjective

going from place to place in order to find people to attack or things to steal or destroy

mortal

adjective

likely to end with someone’s death

mortally

adverb

in a way that is likely to cause death

nasty

adjective

serious or dangerous

negative

adjective

harmful, or bad

noxious

adjective

harmful, or poisonous

overactive

adjective

causing harm by being too active

parlous

adjective

very formal full of dangers or difficulties

perilously

adverb

mainly literary in a way that is dangerous or that can cause serious problems

pernicious

adjective

formal very dangerous or harmful, especially to someone’s moral character

poisonous

adjective

containing poison

poisonous

adjective

causing a lot of damage or harm

precarious

adjective

likely to change or become dangerous without warning

precarious

adjective

not safe or likely to fall

prejudicial

adjective

formal harmful to someone or something

serious

adjective

bad or dangerous enough to make you worried

seriously

adverb

in a way that is bad or dangerous enough to make you worried

sticky

adjective

informal a sticky situation is difficult or dangerous

suicidal

adjective

very dangerous, and likely to lead to serious problems or to death

suicide

noun

used about an attack that will kill the person who makes it

suspect

adjective

looking dangerous or illegal

terrible

adjective

causing or involving serious harm or damage

threatening

adjective

showing or saying that someone is likely to do something that will harm you

too hot to handle

too difficult or dangerous to get involved with

toxic

adjective

poisonous and harmful to people, animals, or the environment

treacherous

adjective

very dangerous, especially because the dangers are not obvious

undesirable

adjective

bad, or harmful

unsound

adjective

not safe

volatile

adjective

a volatile situation can suddenly change or become more dangerous

wanton

adjective

formal causing harm or damage for no reason

Antonyms

BuzzWord

hygge

a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

BuzzWord Article

Open Dictionary

sofar

a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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