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 After Urzúa’s death in 1991, his descendants used the home less and less, gradually surrendering whole rooms to decay and disrepair. New York Times, 27 Sep. 2021 When the Universe is a few picoseconds old, top quarks and antiquarks stop being created, and quickly decay away. Ethan Siegel, Forbes, 2 Sep. 2021 Closed to students and staff in 1984, the once-bustling learning hub has for decades done nothing but decay and rot. Mandy Mclaren, The Courier-Journal, 12 Aug. 2021 Between the end of 1842 and beginning of 1843, somewhere between 16 and 20 consumption patients filed into the dark recesses of Mammoth Cave—where humidity fluctuates, but timber doesn’t rot and dead animals never decay. Leo Deluca, Smithsonian Magazine, 14 July 2021 Levine doesn’t hide aging and decay, yet her work is a vision of perfection. Washington Post, 11 June 2021 Hey Humans Natural Toothpaste Wintermint Chill Created by Jada Pinkett-Smith, this toothpaste is filled with natural ingredients like coconut oil, which works to fight bacteria and decay in the mouth while also gently whitening teeth. Akili King, Vogue, 10 June 2021 This is called bloom, a beneficial naturally occurring substance that protects the fruit from moisture and decay Romano explains. Stefani Sassos, Ms, Rdn, Cso, Good Housekeeping, 26 May 2021 The bacteria of tooth decay colonize the oral cavity early in life and are transmitted from mother to baby. Jeffrey Ebersole, The Conversation, 18 May 2021 Recent Examples on the Web: Noun But Mexico's refusal to grant visas for the DEA agents is one of the small but significant irritants to the relationship right now, which is contributing to a decay in the security relationship between the bordering countries. Evan Perez, CNN, 6 Oct. 2021 Two startups, Videa Health and Overjet, both have roots at MIT and are developing software to spot tooth decay and gum disease earlier on dental X-rays. BostonGlobe.com, 9 Sep. 2021 New York City's once-beautiful Washington Square Park is succumbing to urban decay. Lucas Manfredi, Fox News, 26 July 2021 And that 40% of children have tooth decay by kindergarten? Anchorage Daily News, 25 July 2021 The trail starts near the old observation tower (which is closed due to significant wood decay) and winds for 2.8 miles through the park, including along Sturgeon Bay. Chelsey Lewis, Milwaukee Journal Sentinel, 21 July 2021 The burning of the sugars is via acid, and acid wears away tooth enamel which causes tooth decay. Sudiksha Kochi, USA TODAY, 6 July 2021 Its heavy concentration of feldspar grains — known as arkose — means the rock is inevitably prone to chemical decay. Washington Post, 2 Apr. 2021 In June 2016 the bridge was weight-limited due to decay of the timber structure. oregonlive, 24 Aug. 2020

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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Dictionary Entries Near decay

Decauville

decay

decayable

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Statistics for decay

Last Updated

23 Oct 2021

Cite this Entry

“Decay.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decay. Accessed 27 Oct. 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.
: 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.
: 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

decay

intransitive verb
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)

More from Merriam-Webster on decay

Nglish: Translation of decay for Spanish Speakers

Britannica English: Translation of decay for Arabic Speakers

Britannica.com: Encyclopedia article about decay

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