adjective
deleterious
del-ih-TEER-ee-uss
Deleterious (adjective) means causing harm or damage, especially gradually and to health, an environment or a system. Example: “Long hours of night work have a deleterious effect on the heart.”
adjective
1
Causing harm or damage, especially gradually and to health, an environment or a system.
"Long hours of night work have a deleterious effect on the heart."
"Overgrazing proved deleterious to the fragile hillside soil."
How to use deleterious
Learner’s notesIn plain EnglishBad for you, in a way that does real damage.
When to use it
Formal; most at home in scientific, medical and academic writing.
Easily confused with
Common pairings
deleterious effect
deleterious impact
deleterious to health
deleterious consequences
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Long hours of night work have a _____ effect on the heart.
Etymology
From Greek dēlētērios 'noxious, destructive', from dēleisthai 'to hurt'.
Synonyms
View more →Antonyms
Related words
Rhymes for deleterious
See all rhymes for deleterious →Frequently asked questions
What is the difference between deleterious and detrimental?
They are close in meaning and often interchangeable. Deleterious leans towards physical or biological damage and is the commoner word in medicine and science; detrimental is more general and is used freely about careers, reputations and business.
Is deleterious too formal for everyday writing?
It is a formal word. In conversation or plain-English copy, harmful or damaging usually reads better; keep deleterious for academic, medical and legal prose.
What is the meaning of deleterious?
"deleterious" (adjective) means causing harm or damage, especially gradually and to health, an environment or a system.
What is another word for deleterious?
Other words for "deleterious" include harmful, damaging, injurious, detrimental, destructive, hurtful.
