# noxious

/ˈnɑkʃəs/ (US) · /nˈɒkʃəs/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/noxious
Updated: 2026-05-19

## Definition

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.

For teachers: 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.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.