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nul·li·fy

(nŭlə-fī′)

tr.v. nul·li·fied, nul·li·fy·ing, nul·li·fies

1. To make null; invalidate.

2. To counteract the force or effectiveness of.

[Latin nūllificāre, to despise : nūllus, none; see ne in the Appendix of Indo-European roots + -ficāre, -fy.]

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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