- to become decomposed; rot: vegetation that was decaying.
- to decline in excellence, prosperity, health, etc.; deteriorate.
- Physics. (of a radioactive nucleus) to change spontaneously into one or more different nuclei in a process in which atomic particles, as alpha particles, are emitted from the nucleus, electrons are captured or lost, or fission takes place.
- to cause to decay or decompose; rot: The dampness of the climate decayed the books.
- decomposition; rot: Decay made the wood unsuitable for use.
- a gradual falling into an inferior condition; progressive decline: the decay of international relations; the decay of the Aztec civilizations.
- decline in or loss of strength, health, intellect, etc.: His mental decay is distressing.
- Also called disintegration, radioactive decay. Physics. a radioactive process in which a nucleus undergoes spontaneous transformation into one or more different nuclei and simultaneously emits radiation, loses electrons, or undergoes fission.
- Aerospace. the progressive, accelerating reduction in orbital parameters, particularly apogee and perigee, of a spacecraft due to atmospheric drag.
Origin of decay
SynonymsSee more synonyms on Thesaurus.com
Examples from the Web for decay
Their decay proceeded without a ready supply of oxygen, producing hydrocarbons like methane instead of oxygen-bearing molecules.Methane on Mars: Life or Just Gas?
Matthew R. Francis
December 17, 2014
Witnesses say there were at least six bodies piled together inside this one tiled room where the air is poisonous with decay.Who Is Behind Gaza's Mass Execution?
August 1, 2014
In the summer heat, the smell of decay was beginning to spread.In the Killing Fields of Ukraine with Children Who Saw the MH17 Horror
July 20, 2014
Theaters were quickly abandoned, left to decay and sometimes destroyed.Kabul's Major Motion Picture: Cinema's Rebirth in Afghanistan
April 13, 2014
To begin with there is the general indifference to the decay of democracy.George Orwell’s Letter on Why He Wrote ‘1984’
August 12, 2013
She was aware of the creeping fret, the poisons and obstructions of decay.Life and Death of Harriett Frean
To get it all you must live there, to be interpenetrated by its glory of decay.
Old age and decay, bad enough in themselves, we intensify by our habits of mind.
Will you have nothing to remember him by but his ruin and decay?Little Dorrit
Is the something else, the decay of dead citizens in the vaults below?The Uncommercial Traveller
- to decline or cause to decline gradually in health, prosperity, excellence, etc; deteriorate; waste away
- to rot or cause to rot as a result of bacterial, fungal, or chemical action; decompose
- Also: disintegrate (intr) physics
- (of an atomic nucleus) to undergo radioactive disintegration
- (of an elementary particle) to transform into two or more different elementary particles
- (intr) physics (of a stored charge, magnetic flux, etc) to decrease gradually when the source of energy has been removed
- the process of decline, as in health, mentality, beauty, etc
- the state brought about by this process
- decomposition, as of vegetable matter
- rotten or decayed matterthe dentist drilled out the decay
- See radioactive decay
- a spontaneous transformation of an elementary particle into two or more different particles
- of an excited atom or molecule, losing energy by the spontaneous emission of photons
- physics a gradual decrease of a stored charge, magnetic flux, current, etc, when the source of energy has been removedSee also time constant
- music the fading away of a note
Word Origin and History for decay
late 15c., "to decrease," from Anglo-French decair, Old North French decair (Old French decheoir, 12c., Modern French déchoir) "to fall, set (of the sun), weaken, decline, decay," from Vulgar Latin *decadere "to fall off," from de- (see de-) + Latin cadere "to fall" (see case (n.1)). Meaning "decline, deteriorate" is c.1500; that of "to decompose, rot" is from 1570s. Related: Decayed; decaying.
mid-15c., "deterioration, decline in value," from decay (v.). Meaning "gradual decrease in radioactivity" is from 1897.
- The destruction or decomposition of organic matter as a result of bacterial or fungal action; rot.
- Dental caries.
- The loss of information that was registered by the senses and processed into the short-term memory system.
- Radioactive decay.
- To break down into component parts; rot.
- To disintegrate or diminish by radioactive decay.
- To decline in health or vigor; waste away.
- The breaking down or rotting of organic matter through the action of bacteria, fungi, or other organisms; decomposition.
- The spontaneous transformation of a relatively unstable particle into a set of new particles. For example, a pion decays spontaneously into a muon and an antineutrino. The decay of heavy or unstable atomic nuclei (such as uranium or carbon-10) into more stable nuclei and emitted particles is called radioactive decay. The study of particle decay is fundamental to subatomic physics. See more at fundamental force radioactive decay.
- To undergo decay.