a. Capable of being resolved into constituent elements. [ 1913 Webster ]

v. t. [ imp. & p. p. Decomposed p. pr. & vb. n. Decomposing. ] [ Cf. F. décomposer. Cf. Discompose. ] To separate the constituent parts of; to resolve into original elements; to set free from previously existing forms of chemical combination; to bring to dissolution; to rot or decay. [ 1913 Webster ]

v. i. To become resolved or returned from existing combinations; to undergo dissolution; to decay; to rot. [ 1913 Webster ]

a. (Zool.) Separated or broken up; -- said of the crest of birds when the feathers are divergent. [ 1913 Webster ]

a. [ Pref. de- (intens.) + composite. ] 1. Compounded more than once; compounded with things already composite. [ 1913 Webster ]

2. (Bot.) See Decompound, a., 2. [ 1913 Webster ]

n. Anything decompounded. [ 1913 Webster ]

Decomposites of three metals or more. Bacon. [ 1913 Webster ]

n. [ Pref. de- (in sense 3 intensive) + composition: cf. F. décomposition. Cf. Decomposition. ] 1. The act or process of resolving the constituent parts of a compound body or substance into its elementary parts; separation into constituent part; analysis; the decay or dissolution consequent on the removal or alteration of some of the ingredients of a compound; disintegration; as, the decomposition of wood, rocks, etc. [ 1913 Webster ]

2. The state of being reduced into original elements. [ 1913 Webster ]

3. Repeated composition; a combination of compounds. [ Obs. ] [ 1913 Webster ]

Decomposition of forces. Same as Resolution of forces, under Resolution. --
Decomposition of light, the division of light into the prismatic colors. [ 1913 Webster ]

adj. causing organic decay. [ WordNet 1.5 ]