a. [ L. defunctus, p. p. of defungi to acquit one's self of, to perform, finish, depart, die; de + fungi to perform, discharge: cf. F. défunt. See Function. ] 1. Having finished the course of life; dead; deceased. “Defunct organs.” Shak. [ 1913 Webster ]

The boar, defunct, lay tripped up, near. Byron. [ 1913 Webster ]

2. No longer in effect or use; no longer operating; as, a defunct business; a defunct law. [ PJC ]

n. A dead person; one deceased. [ 1913 Webster ]

n. [ L. defunctio performance, death. ] Death. [ Obs. ] [ 1913 Webster ]

After defunction of King Pharamond. Shak. [ 1913 Webster ]

a. Funereal. [ Obs. ] “Defunctive music.” Shak. [ 1913 Webster ]

v. t. [ Cf. Diffuse. ] 1. To disorder; to make shapeless. [ Obs. ] Shak. [ 1913 Webster ]

2. To remove the fuse from; to deactivate (a bomb or other explosive device) or make it ineffective.
Syn. -- deactivate. [ WordNet 1.5 +PJC ]

3. To make less dangerous; as, to defuse a tense confrontation between demonstrators and police. [ PJC ]

n. 1. The act of deactivating or making ineffective (as a bomb).
Syn. -- deactivation. [ WordNet 1.5 ]