The definition of noxious is something very unpleasant or something poisonous.
An example of a noxious gas is carbon monoxide.
- harmful to the health; injurious: a noxious gas
- morally injurious; corrupting; unwholesome
Origin of noxiousClassical Latin noxius from noxa, injury, hurt from nocere, to hurt, injure: see necro-
- Harmful to living things; injurious to health: noxious chemical wastes.
- Harmful to the mind or morals; corrupting: noxious ideas.
Origin of noxiousMiddle English noxius from Latin from noxa damage ; see nek-1 in Indo-European roots.
- Nouns to which "noxious" is often applied: substance, chemical, fume, gas, odor, plant, weed, animal, stimulus, stimulation.
From noxius (“hurtful, injurious"), from noxa (“hurt, injury"), from nocere (“to hurt, injure"); see nocent.