Definition of deleterious in English:



  • Causing harm or damage.

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