DISSOCIATION

noun the act of dissociating or disuniting; a state of separation; disunion.

2. dissociation ·noun the process by which a compound body breaks up into simpler constituents;

— said particularly of the action of heat on gaseous or volatile substances; as, the dissociation of the sulphur molecules; the dissociation of ammonium chloride into hydrochloric acid and ammonia.