The act of nullifying; a rendering void and of no effect, or no legal effect.
The nullification crisis in U.S. history, confrontation between the state of South Carolina and the federal government in 1832–33 over the former's attempt to declare null and void within the state the federal Tariffs of 1828 and 1832.
Surgical removal of genitals (and sometimes nipples) as a form of body modification; a person who has undergone this surgery is a nullo.
The cancellation, erasure or deletion of something.
The cancellation of the function, structure, or both of a vessel or organ; for example, the occlusion of the lumen of a duct, blood vessel, or lymphatic vessel, be it solely functional (as when squeezed by nearby mass effect or inflammation) or both structural and functional (as when clogged with thrombus, embolus, or fibrosis).
The total destruction of something.