adjective \ˈnäk-shəs\

: harmful to living things

Full Definition of NOXIOUS

a :  physically harmful or destructive to living beings <noxious waste>
b :  constituting a harmful influence on mind or behavior; especially :  morally corrupting <noxious doctrines>
nox·ious·ly adverb
nox·ious·ness noun

Examples of NOXIOUS

  1. <mixing bleach and ammonia can cause noxious fumes that can seriously harm you>
  2. <noxious smog that for years has been encrusting the historic cathedral with soot>

Origin of NOXIOUS

Middle English noxius, from Latin, from noxa harm; akin to Latin nocēre to harm, nec-, nex violent death, Greek nekros dead body
First Known Use: 15th century

Other Ecology Terms

Malthusian, anthropogenic, biomass, carbon footprint, crepuscular, niche, sere, symbiosis, taiga, tundra


adjective \ˈnäk-shəs\   (Medical Dictionary)

Medical Definition of NOXIOUS

: physically harmful or destructive to living beings <noxious wastes>


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