ENGLISH
REFERENCE

deleterious

adj.
C1 Advanced US //ˌdɛɫəˈtɪɹiəs// UK //dɪlɪtˈiəɹɪəs// dele·te·ri·ous Formal

adj. harmful or damaging to something. You use this to describe things that have a bad effect on health, the environment, or a situation.

adj. causing harm or damage; having a detrimental effect. Often used in formal or scientific contexts to describe negative impacts on health, the environment, or social structures.


SIMPLE

The smoke from the factory has a deleterious effect on the local birds.

CONTEXTUAL

Prolonged exposure to high levels of noise can have a deleterious impact on a person's mental health and hearing.

COMPLEX

While the initial economic stimulus provided a temporary boost, the long-term reliance on debt proved deleterious to the country's fiscal stability and international credit rating.

Synonyms
Origin

Adapted borrowing (1640s; 1582 as deletorious) of New Latin dēlētērius, dēlētōrius + -ous, from Ancient Greek δηλητήριος (dēlētḗrios, “noxious, deleterious”), from δηλητήρ (dēlētḗr, “a destroyer”), from δηλέομαι (dēléomai, “I hurt, damage, spoil, waste”). Not related to delete or deleble. Doublet of deletery.

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