nullification

noun

1. an act or instance of nullifying.
2. the state of being nullified.
3. (often initial capital letter) the failure or refusal of a U.S. state to aid in enforcement of federal laws within its limits, especially on Constitutional grounds.

n.in U.S. political sense of “a state’s refusing to allow a federal law to be enforced,” 1798, in Thomas Jefferson; from Late Latin nullificationem (nominative nullificatio) “a making as nothing,” from past participle stem of nullificare (see nullify). Related: Nullificationist. The doctrine that states can set aside federal laws. Urged in the late 1820s by John C. Calhoun, nullification precipitated a crisis between Calhoun and President Andrew Jackson. The doctrine was foreshadowed by Thomas Jefferson’s draft of the Kentucky Resolutions. (See Virginia and Kentucky Resolutions.)