Deleterious Meaning
/ˌdɛl.ɪˈtɪə̯.ɹi.əs/Definition, CEFR level B2, pronunciation, examples, and quiz.
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Definition
adjHarmful, often in a subtle or unexpected way.
adjHaving lower fitness.
Sentence Examples
We cannot continue to ignore the deleterious effects of these policies on our country.
Insufficient illumination is deleterious to ocular health.
This would have a deleterious effect on our ability to organize.
CEFR Practice Quiz
Smoking has a ____ effect on lung health, often leading to chronic diseases over time.
CEFR Practice Quiz (Alternate)
We cannot continue to ignore the ____ effects of these policies on our country.
Word Origin & History
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.
Literary Quotations & Historical Citations
"Or might it suffice him, that every wholesome growth should be converted into something deleterious and malignant at his touch?"
— 1850, Nathaniel Hawthorne, “chapter XV”, in The Scarlet Letter:
"A trolleybus service was established by the London Passenger Transport Board between North Woolwich and Stratford on February 6, 1938, and had a deleterious effect on railway passenger traffic."
— 1946 May and June, J. G. Holmes, “The North Woolwich Branch”, in Railway Magazine, page 176:
"The advent of the smartphone and its cousin the tablet was followed quickly by hand-wringing about the deleterious effects of “screen time.” But the impact of these devices has not been fully appreciated, and goes far beyond the usual concerns about curtailed attention spans."
— 2017 September, Jean M. Twenge, “Have Smartphones Destroyed a Generation?”, in The Atlantic:
Explore More B2 Vocabulary Words
CEFR Practice Quiz
Smoking has a ____ effect on lung health, often leading to chronic diseases over time.
CEFR Practice Quiz (Alternate)
We cannot continue to ignore the ____ effects of these policies on our country.