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 Interesting being historic, detailed, decaying, and interesting colors. Baltimore Sun Staff, baltimoresun.com, "What makes a good photo? You know it when you feel it, Photographer of the Month Kayla James says.," 1 Oct. 2019 This attention to detail, keeping the French Quarter trapped in a calcified past, requires money and wherewithal, of course, that other parts of the city, languishing and decaying, do not have. Sarah M. Broom, The New Yorker, "Who Stays Gone, and Who Can Afford to Return," 12 Aug. 2019 Alaska has by far the highest rate of botulism in the United States—there are 800 times more cases per capita there—and some have been linked to eating stranded, decaying, or fermented whale and seal. Craig Welch, National Geographic, "More people are eating marine animals—with deadly results," 22 May 2019 It gets released from the ground as uranium decays in rocks and soil. Beth Nakamura, The Oregonian - OregonLive.com, "The government urges private homeowners to test for cancer-causing radon gas. For low-income tenants of public housing, the government ignores its own advice.," 22 Nov. 2019 In other words, quantum knots might not be dynamically stable, winking out of existence before their superfluid medium decays. Jennifer Ouellette, Ars Technica, "Physicists capture first footage of quantum knots unraveling in superfluid," 15 Nov. 2019 Corpses of enemy soldiers lay decaying in the mire. oregonlive, "Veterans Day 2019: Remembering Oregon’s 96th Infantry Division," 10 Nov. 2019 Conversely, if the power law decayed any faster, the neural representations would become lower-dimensional. Quanta Magazine, "A Power Law Keeps the Brain’s Perceptions Balanced," 22 Oct. 2019 Lebanon's decaying infrastructure, which includes long and frequent power outages, has meant that living standards have dropped for many Lebanese. Tamara Qiblawi, CNN, "Lebanon's Hariri gives opponents 72 hours to find economic solutions as protests grow," 18 Oct. 2019 Recent Examples on the Web: Noun This latest finding indicates that time may be an important factor, given the knots' rate of decay. Jennifer Ouellette, Ars Technica, "Physicists capture first footage of quantum knots unraveling in superfluid," 15 Nov. 2019 The mansion house is just beginning to show serious signs of decay, but may be easily rescued. Mary Grace Keller, baltimoresun.com/maryland/carroll, "Historical home that caught fire in Sykesville has roots reaching through centuries," 8 Nov. 2019 To him, what came after WASPdom was not a culture but a product of decay. Doug Henwood, Harper's magazine, "To Serve Is to Rule," 28 Oct. 2019 The Egyptian man’s head, blackened from decay but still sporting white teeth, remains uncovered from that time. Washington Post, "Knock yourself out in the Ether Dome," 9 Oct. 2019 In the long run, all participants in this economy except for the very richest one will see their wealth decay exponentially. Bruce M. Boghosian, Scientific American, "Is Inequality Inevitable?," 1 Nov. 2019 The influx would have triggered algae growth, and when these algae died, their decay removed oxygen from the oceans to form what are known as dead zones. Michael Greshko, National Geographic, "What are mass extinctions, and what causes them?," 30 Sep. 2019 Those who did were often ignored, their work forgotten or left to decay in attics. Charlotte Gordon, Washington Post, "Female artists have been overlooked and ignored. This book wants to correct that.," 5 Sep. 2019 The surgery and psychiatric wards have both been left to decay and give way to nature (and vandals), and the result looks like something straight out of American Horror Story—definitely not an enjoyable day trip for the easily spooked. Caitlin Morton, Condé Nast Traveler, "Creepy Catacombs, Islands of Dolls, and 18 Other Terrifying Places for Thrill Seekers," 4 Sep. 2019

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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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

10 Dec 2019

Cite this Entry

“Decay.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/decay. Accessed 11 December 2019.

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More Definitions for decay

decay

verb
How to pronounce decay (audio)

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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More from Merriam-Webster on decay

Thesaurus: All synonyms and antonyms for decay

Rhyming Dictionary: Words that rhyme with decay

Spanish Central: Translation of 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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