Definition of noxious
- noxious waste
- noxious fumes
- noxious doctrines
mixing bleach and ammonia can cause noxious fumes that can seriously harm you
noxious smog that for years has been encrusting the historic cathedral with soot
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'noxious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 15th centurySee Words from the same year
: harmful to living things
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