Simple Definition of pollutant

from our Learner's Dictionary

pollutant

noun

pəˈluːtn̩t

plural pollutants

: a substance that makes land, water, air, etc., dirty and not safe or suitable to use : something that causes pollution

air/water pollutants

environmental/industrial pollutants

chemical/toxic pollutants

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“Pollutant.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/pollutant. Accessed 16 Apr. 2026.

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