Definition of deleterious in English:



  • Causing harm or damage.

    ‘divorce is assumed to have deleterious effects on children’
    • ‘So what can be done to wind back the deleterious effects of confidentiality agreements on public safety?’
    • ‘Any move is likely to have a deleterious effect on their health and will certainly adversely affect the quality of their life.’
    • ‘Moreover, scientific studies on choking reveal no deleterious after effects.’
    • ‘Actions taken because of the fear of this older future are already having deleterious effects for lots of older people.’
    • ‘In fact, the war itself would have had a deleterious effect on tourism, one would have thought.’
    • ‘The deleterious effect is that there can be no public scrutiny and comment on the conduct of the police investigation.’
    • ‘The resulting instability often has deleterious effects on the children of the relationship.’
    • ‘I think, to that degree, it may have had a deleterious effect upon the medium since then.’
    • ‘The virus causes about 1 million deaths a year due to its deleterious effects on the liver.’
    • ‘It is currently unknown whether the deleterious effects of fats are limited to specific fatty acids.’
    • ‘Nor do they show evidence of any long-term deleterious effect in children attending day-care from an early age.’
    • ‘In general, these drugs have no deleterious effects on training or competition.’
    • ‘This type of genetic shuffling may have unpredictable, often deleterious effects.’
    • ‘We should vigorously oppose such a show, which can only have a deleterious effect on the moral and spiritual climate of our city.’
    • ‘As for carbon dioxide emission - if this does have a deleterious effect, how should we deal with the problem?’
    • ‘Special tax treatment for health benefits has several deleterious effects.’
    • ‘The world situation has had deleterious effects on a couple of international film festivals this week.’
    • ‘A healthy person can consume a large quantity of water without any deleterious effect.’
    • ‘Some deleterious effects ascribed to lead may include contributions from other metals.’
    • ‘And finally, it examines the deleterious effect that this might have on the performer and the people around them.’
    harmful, damaging, detrimental, injurious, inimical, hurtful, bad, adverse, disadvantageous, unfavourable, unfortunate, undesirable
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Mid 17th century: via medieval Latin from Greek dēlētērios ‘noxious’ + -ous.