per ‧ ni ‧ cious /pəˈnɪʃəs $ pər-/ BrE AmE adjective formal
[ Date: 1500-1600 ; Language: French ; Origin: pernicieux , from Latin perniciosus , from pernicies 'destruction' , from nex 'violent death' ]
very harmful or evil, often in a way that you do not notice easily:
the pernicious effects of poverty
the media’s pernicious influence
—perniciously adverb
• • •
THESAURUS
▪ 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