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verb de·com·pose \ˌdē-kəm-ˈpōz\

Simple Definition of decompose

  • : to cause something (such as dead plants and the bodies of dead animals) to be slowly destroyed and broken down by natural processes, chemicals, etc.

  • : to cause something (such as a chemical) to be separated into smaller or simpler parts

Source: Merriam-Webster's Learner's Dictionary

Full Definition of decompose

  1. transitive verb
  2. 1 :  to separate into constituent parts or elements or into simpler compounds <decompose water by electrolysis> <decompose a word into its base and affixes>

  3. 2 :  rot

  4. intransitive verb
  5. :  to break up into constituent parts by or as if by a chemical process :  decay, rot <fruit decomposes>

decomposability play \-ˌpō-zə-ˈbi-lə-tē\ noun
decomposable play \-ˈpō-zə-bəl\ adjective
decomposition play \(ˌ)dē-ˌkäm-pə-ˈzi-shən\ noun

Examples of decompose in a sentence

  1. Bacteria and fungi help decompose organic matter.

  2. the smell of decomposing leaves

  3. The compound will decompose in the presence of light.

Origin of decompose

French décomposer, from dé- de + composer to compose

First Known Use: 1718

Synonym Discussion of decompose

decay, decompose, rot, putrefy, spoil mean to undergo destructive dissolution. decay implies a slow change from a state of soundness or perfection <a decaying mansion>. decompose stresses a breaking down by chemical change and when applied to organic matter a corruption <the strong odor of decomposing vegetation>. rot is a close synonym of decompose and often connotes foulness <fruit was left to rot in warehouses>. putrefy implies the rotting of animal matter and offensiveness to sight and smell <corpses putrefying on the battlefield>. spoil applies chiefly to the decomposition of foods <keep the ham from spoiling>.

Other Microbiology Terms

DECOMPOSE Defined for Kids


verb de·com·pose \ˌdē-kəm-ˈpōz\

Definition of decompose for Students


  1. 1 :  to break down or be broken down into simpler parts or substances especially by the action of living things (as bacteria and fungi) <Leaves decomposed on the forest floor.>

  2. 2 :  to separate a substance into simpler compounds <Water can be decomposed into hydrogen and oxygen.>

Medical Dictionary


verb de·com·pose \ˌdē-kəm-ˈpōz\

Medical Definition of decompose

decomposed; decomposing

  1. transitive verb

  2. :  to separate into constituent parts or elements or into simpler compounds <decompose water by electrolysis>

  3. intransitive verb

  4. :  to undergo chemical breakdown :  decay, rot <fruit decomposes>

decomposability \-ˌpō-zə-ˈbil-ət-ē\play noun plural decomposabilities
decomposable \-ˈpō-zə-bəl\play adjective

Seen and Heard

What made you want to look up decompose? Please tell us where you read or heard it (including the quote, if possible).


to dishevel or rumple

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