The Collaborative International Dictionary of English v.0.48:
deactivation \de*ac`ti*va"tion\, n. The act or process of deactivating. [PJC]WordNet (r) 3.0 (2006):
deactivation n 1: breaking up a military unit (by transfers or discharges) [syn: deactivation, inactivation] 2: the act of deactivating or making ineffective (as a bomb) [syn: deactivation, defusing] [ant: activation]