deleterious C2+ Topic:Safety & Risk US /ˌdɛləˈtɪriəs/ UK /ˌdɛlɪˈtɪəriəs/ See IPA manual Meanings 1 adj causing harm or damage, especially gradually Smoking has well-documented deleterious effects on health. Thesaurus Synonyms 1 adj · causing harm or damage,... harmfuldamaginginjuriousdetrimentaldestructivenoxiousperniciousbaneful ↔ Opposites beneficialhelpfulsalutaryadvantageouswholesome Word family Derived forms deleteriouslydeleteriousness Etymology AI details From Medieval Latin deleterius, from Greek dēlētērios ('noxious, destructive'), from dēlēter ('destroyer'), from dēleisthai ('to hurt, injure'). dēlētērios Ancient Greek dēleisthai Ancient Greek View etymology graph -> Topics Safety & Risk Word Formation & Derivatives External links Cambridge Dictionary Wiktionary Google Images # deleterious **Type:** Word **Level:** C2+ **Part of speech:** adj **IPA (US):** /ˌdɛləˈtɪriəs/ **IPA (UK):** /ˌdɛlɪˈtɪəriəs/ ## Meanings 1. causing harm or damage, especially gradually ## Examples - Smoking has well-documented deleterious effects on health. ## Synonyms - harmful - damaging - injurious - detrimental - destructive - noxious - pernicious - baneful ## Antonyms - beneficial - helpful - salutary - advantageous - wholesome ## Derived Forms - deleteriously - deleteriousness ## Roots and Affixes - Root: dēlētērios - Root: dēleisthai ## Etymology From Medieval Latin deleterius, from Greek dēlētērios ('noxious, destructive'), from dēlēter ('destroyer'), from dēleisthai ('to hurt, injure'). ## AI Etymology Deleterious comes from Medieval Latin deleterius, from Greek dēlētērios ('noxious, destructive'), from dēlēter ('destroyer'), from dēleisthai ('to hurt, injure'). The historical trail runs through Ancient Greek dēlētērios and Ancient Greek dēleisthai. In modern use it means causing harm or damage, especially gradually. Derived formations include deleteriously, deleteriousness. ## Topics - Safety & Risk - Word Formation & Derivatives markdown