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nox·ious

(nŏkshəs)

adj.

1. Harmful to living things; injurious to health: noxious chemical wastes.

2. Harmful to the mind or morals; corrupting: noxious ideas.

[Middle English noxius, from Latin, from noxa, damage; see nek-¹ in the Appendix of Indo-European roots.]

noxious·ly adv.

noxious·ness n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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