Definition of nullification:
- negation (part of speech: noun)
annulment (part of speech: noun)
- "Government and Administration of the United States", Westel W. Willoughby and William F. Willoughby.
- "John Marshall and the Constitution A Chronicle of the Supreme Court, Volume 16 In The Chronicles Of America Series", Edward S. Corwin.
- "The Rise and Fall of the Confederate Government, Vol. 1 (of 2)", Jefferson Davis.