Deleterious
/ˌdɛlɪˈtɪəriəs/noun
Harmful or damaging, especially in a gradual or subtle way.
Did you know?Deleterious comes through Greek, where its root is tied to the idea of ruining or destroying, showing how ancient languages often encoded danger directly into everyday vocabulary.
Etymological Timeline
Ancient Greek
Greek
δηλητηριώδης (dēlētēriṓdēs)
“poisonous, noxious”
Late Latin
Latin
deleterius
“harmful, hurtful”
Middle French
French
délétère
“harmful, deadly”
16th Century
English
deleterious
“harmful, injurious”
Modern English
English
deleterious
“harmful or damaging, especially slowly or subtly”
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