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Added 9 October 2026

harmful

/ˈhɑːmfl̩/ adjective

In Latin: nocuus, noxius Wiktionary

adjective Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about harmful at Wordnik → Where our words come from →

Causing or likely to cause harm or damage; injurious.
Wear a hat to protect your skin from harmful sunlight.

Origin

From Middle English harmful, from Old English *hearmful (suggested by hearmfullīċ (“harmful; hurtful”)), equivalent to harm + -ful. Cognate with German harmvoll, Danish harmfuld, Swedish harmfull.

From Wiktionary, via Kaikki.org (CC BY-SA)

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