Christmas Fern – Polystichum acrostichoides

Biology and ecology

Decomposition is the process through which organic matter is broken down into simpler molecules.
Biodegradation

Decomposition, decompose may also refer to:

Chemical decomposition or analysis, in chemistry, is the fragmentation of a chemical compound into elements or smaller compounds
- Thermal decomposition, chemical decomposition caused by heat

Decomposition of time series, a statistical task that deconstructs a time series into several components
Doob decomposition theorem of an integrable, discrete-time stochastic process
Doob–Meyer decomposition theorem of a continuous-time sub- or supermartingale
Fourier decomposition, re-expressing a given periodic function as the sum of a series of trigonometric functions
Hahn decomposition theorem of a measure space
- Jordan decomposition theorem of a signed measure
Helmholtz decomposition, decomposition of a vector field
Indecomposable continuum
Lebesgue's decomposition theorem, decomposition of a measure
Lie group decomposition, used to analyse the structure of Lie groups and associated objects
Manifold decomposition, decomposition of manifolds
- JSJ decomposition, or toral decomposition, a decomposition of 3-manifolds
Matrix decomposition, a factorization of a matrix into a product of matrices
- LU decomposition, a type of matrix factorization
Permutation decomposition, decomposition of a permutation into disjoint cycles
Primary decomposition, decomposition of ideals into primary ideals
Vector decomposition, decomposition of vectors into components or coordinates of basis vectors
Wavelet decomposition, re-expressing a given function as the sum of a series of wavelet functions

Decomposition (computer science), or factoring; the process of breaking a complex problem down into easily understood and achievable parts
- Decomposition method (disambiguation), solutions of various problems and design of algorithms
- Functional decomposition, expressing a function as the composition of two functions
Semantic decomposition (natural language processing)
Decompositions: Volume Number One, the second studio album by American screamo band Circle Takes the Square
Zersetzung, or decomposition, a debilitative psychological warfare technique utilised by the Stasi intelligence agency in East Germany