English Reference

Word

noxious

Phoneticsnox·ious

US/ˈnɑkʃəs/

UK/nˈɒkʃəs/

Definition

adj. harmful to your health or dangerous to living things. You use this to describe things like bad smells, poisonous plants, or chemicals that can make you sick.

adj. harmful to health or life; poisonous or injurious. Often describes substances that cause physical or biological damage upon contact or inhalation.

Examples

“The factory released noxious fumes into the air.”

“The gardener warned that the plant was noxious and could cause skin irritation if touched.”

“The rapid expansion of industrial zones led to the accumulation of noxious gases in the valley, significantly degrading the local air quality and affecting the health of nearby residents.”

Examples

simple

“The factory released noxious fumes into the air.”

contextual

“The gardener warned that the plant was noxious and could cause skin irritation if touched.”

complex

“The rapid expansion of industrial zones led to the accumulation of noxious gases in the valley, significantly degrading the local air quality and affecting the health of nearby residents.”

Real-World Examples

“Transtiberim was where “noxious or dangerous industries deliberately kept at a distance from central Rome” were located.”
JSTOR Daily · 17 Aug 2026

Etymology

From Latin noxius (“hurtful, injurious”), from noxa (“hurt, injury”), from nocere (“to hurt, injure”); see nocent.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

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English Reference