decay

verb
de·​cay | \ di-ˈkā How to pronounce decay (audio) \
decayed; decaying; decays

Definition of decay

 (Entry 1 of 2)

intransitive verb

1 : to undergo decomposition decaying fruit Her teeth were decaying. … most isotopes of copper decay quickly, but two are stable: Cu-63 and Cu-65.— David E. Thomas
2 : to decline in health, strength, or vigor Her mind is beginning to decay with age. believes that the moral fiber of our society is decaying
3 : to fall into ruin the city's decaying neighborhoods
4 : to decline from a sound or prosperous condition a decaying empire
5 : to decrease usually gradually in size, quantity, activity, or force The three voices … decayed and died out upon her ear.— Thomas Hardy

transitive verb

1 : to destroy by decomposition wood decayed by bacteria
2 obsolete : to cause to decay : impair Infirmity, that decays the wise …— William Shakespeare

decay

noun

Definition of decay (Entry 2 of 2)

1a : rot The material is … resistant to fire, decay and termites …— Jack McClintock specifically : aerobic decomposition of proteins chiefly by bacteria
b : the product of decay tooth decay
2 : gradual decline in strength, soundness, or prosperity or in degree of excellence or perfection the decay of the public school system
3 : a decline in health or vigor mental decay
4 : a wasting or wearing away : ruin a neighborhood that had fallen into decay
5 : decrease in quantity, activity, or force: such as
a chemistry : spontaneous decrease in the number of radioactive atoms in radioactive material
b physics : spontaneous disintegration (as of an atom or a particle)
6 obsolete : destruction, death … sullen presage of your own decay.— Shakespeare

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Other Words from decay

Verb

decayer noun

Choose the Right Synonym for decay

Verb

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

Examples of decay in a Sentence

Verb the smell of decaying rubbish dead plants and leaves decayed by bacteria She believes that the moral fiber of our society is decaying. our decaying public school system The city's neighborhoods are decaying. Noun the decay of dead plants and leaves She writes about the moral decay of our society. the patient's physical and mental decay The city's neighborhoods are in slow decay.
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Recent Examples on the Web: Verb TikTok is full of cautionary tales—like the woman who claimed that pregnancy made her teeth decay and break off, or the woman who's had to get her labia cut open 26 times because of Bartholin's cysts. Claire Gillespie, Health.com, 5 May 2021 That storage would allow the radioactive isotopes to naturally decay while buying time to develop new treatment techniques. Dennis Normile, Science | AAAS, 13 Apr. 2021 The expanding atmosphere causes drag on orbiting satellites causing their orbits to decay faster. Curtis Roelle, baltimoresun.com/maryland/carroll, 10 Apr. 2021 When tufa forms, uranium is ‘locked’ into the crystal structure and begins to decay to produce thorium. Benjamin Schoville, Quartz, 4 Apr. 2021 Remarkably, when these particles decay, the version that contain b-quarks and the version that contain b-antiquarks have different properties: evidence for a fundamental matter-antimatter asymmetry known as CP-violation. Ethan Siegel, Forbes, 27 Apr. 2021 Prolonged storage would provide more time for some of the radioactive isotopes to decay to less-harmful levels. Eamon Barrett, Fortune, 16 Apr. 2021 However, the severe topping of the tree has led to decay through the heartwood of the trunk. Neil Sperry, San Antonio Express-News, 2 Apr. 2021 The more contact the atmosphere makes with the rocket stage, the faster its orbit will decay. Jeffrey Kluger, Time, 5 May 2021 Recent Examples on the Web: Noun Local tension over the school’s decay reflects a larger truth: America’s small towns have been shrinking, sometimes into nothingness. Michael M. Phillips, WSJ, 10 June 2021 The book ultimately paints an unforgettable portrait of the very real consequences that environmental decay can hold, for nature and humanity alike. Vogue, 29 May 2021 The brown flowers easily blend into the forest floor near rocks and leaf litter and release the decay-like smell to entice pollinators to the flowers' opening, reports Isaac Schultz for Gizmodo. Elizabeth Gamillo, Smithsonian Magazine, 26 May 2021 The contagion may soon experience exponential decay - the opposite of its explosive spread last spring and again in the late fall and winter. Joel Achenbach, Anchorage Daily News, 14 May 2021 Their malicious elders stand in for larger societal decay. Darren Franich, EW.com, 12 Apr. 2021 That pile of mulch causes decay around the base of your tree. Paul Cappiello, The Courier-Journal, 9 Apr. 2021 For delicate fruits and vegetables in the U.S. and Europe, a leading storage hurdle comes immediately after harvest, when temperatures must be lowered quickly to avoid decay. John Flesher, Detroit Free Press, 26 Mar. 2021 In the show, acclaim invites creative decay, but obscurity feels no safer. Katy Waldman, The New Yorker, 25 Feb. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'decay.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of decay

Verb

15th century, in the meaning defined at intransitive sense 4

Noun

15th century, in the meaning defined at sense 2

History and Etymology for decay

Verb and Noun

Middle English, from Anglo-French decaïr, from Late Latin decadere to fall, sink, from Latin de- + cadere to fall — more at chance

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Learn More About decay

Time Traveler for decay

Time Traveler

The first known use of decay was in the 15th century

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Statistics for decay

Last Updated

13 Jun 2021

Cite this Entry

“Decay.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decay. Accessed 17 Jun. 2021.

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More Definitions for decay

decay

verb

English Language Learners Definition of decay

 (Entry 1 of 2)

: to be slowly destroyed by natural processes : to be slowly broken down by the natural processes that destroy a dead plant or body
: to slowly lose strength, health, etc.
of a building, area, etc. : to go slowly from a bad condition to a worse condition : to slowly enter a state of ruin

decay

noun

English Language Learners Definition of decay (Entry 2 of 2)

: the process or result of being slowly destroyed by natural processes
: the slow loss of strength, health, etc.
of a building, area, etc. : the process or result of going slowly from a bad condition to a worse condition

decay

verb
de·​cay | \ di-ˈkā How to pronounce decay (audio) \
decayed; decaying

Kids Definition of decay

 (Entry 1 of 2)

1 : to break down or cause to break down slowly by natural processes Fruit decayed on the ground. Sugar decays teeth.
2 : to slowly worsen in condition The old theater decayed.

decay

noun

Kids Definition of decay (Entry 2 of 2)

1 : the process or result of slowly breaking down by natural processes The schoolhouse being deserted soon fell to decay— Washington Irving, "Sleepy Hollow"
2 : a gradual worsening in condition a decay in manners
3 : a natural change of a radioactive element into another form of the same element or into a different element
de·​cay | \ di-ˈkā How to pronounce decay (audio) \

Medical Definition of decay

 (Entry 1 of 2)

: to undergo decomposition

transitive verb

: to destroy by decomposition

decay

noun

Medical Definition of decay (Entry 2 of 2)

1a : rot sense 1 specifically : aerobic decomposition of proteins chiefly by bacteria
b : the product of decay
2a : spontaneous decrease in the number of radioactive atoms in radioactive material
b : spontaneous disintegration (as of an atom or a nuclear particle)

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