Definition of pernicious in US English:

pernicious

adjective

  • Having a harmful effect, especially in a gradual or subtle way.

    ‘the pernicious influences of the mass media’
    • ‘At the same time, the pernicious influence of new urban cultural patterns could share some of the blame for rural degeneration.’
    • ‘Outside of the identity principle, however, the correlation is both pernicious and ethically dubious.’
    • ‘Instrumental rationality has had a particularly pernicious effect on the environment.’
    • ‘Yet this fear of the pernicious effects of property rights did not last for long.’
    • ‘Yet some faculty perceive the pernicious effects of these forms and want to end them.’
    • ‘At its most extreme whole economies are destroyed by its pernicious influence.’
    • ‘The trouble is that fear is almost as pernicious as perceived danger.’
    • ‘Trying to keep out the pernicious effects of popular culture is a losing battle.’
    • ‘Equally problematic is the pernicious effect of bad design on the environment.’
    • ‘He's correct that the right of jury nullification trumps any worries about the possible pernicious effects of the drug.’
    • ‘Physiological laws can explain the harmful and pernicious effects of deep breathing.’
    • ‘Instead, they say, it is a pernicious and widespread cancer infecting the media and political classes across Europe.’
    • ‘The register will make an important contribution to tackling this pernicious evil.’
    • ‘It also stands for the complete victory of the Buddhist Doctrine over all harmful and pernicious forces.’
    • ‘Just putting some healthier options on the menu doesn't counteract the more pernicious effect a large global corporation has.’
    • ‘What worries me are the pernicious influences on athletes like him.’
    • ‘In fact, it can actually be pernicious because it covers up a reality.’
    • ‘I pretend to teach young people about the pernicious effects of a total surveillance state.’
    • ‘Over the past few months and years, some pernicious myths have started to become a little too popular.’
    • ‘This new form of protectionism has an added pernicious quality.’
    harmful, damaging, destructive, injurious, hurtful, detrimental, deleterious, dangerous, adverse, inimical, unhealthy, unfavourable, bad, evil, baleful, wicked, malign, malevolent, malignant, noxious, poisonous, cancerous, corrupting, ruinous, deadly, lethal, fatal
    View synonyms

Origin

Late Middle English: from Latin perniciosus ‘destructive’, from pernicies ‘ruin’, based on nex, nec- ‘death’.

Pronunciation

pernicious

/pərˈniSHəs//pərˈnɪʃəs/