decay

verb
de·cay | \ di-ˈkā \

Definition of decay 

(Entry 1 of 2)

intransitive verb

1 : to decline from a sound or prosperous condition a decaying empire

2 : to decrease usually gradually in size, quantity, activity, or force The three voices … decayed and died out upon her ear. —Thomas Hardy

3 : to fall into ruin the city's decaying neighborhoods

4 : 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

5 : 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

transitive verb

1 obsolete : to cause to decay : impair infirmity that decays the wise —William Shakespeare

2 : to destroy by decomposition wood decayed by bacteria

decay

noun

Definition of decay (Entry 2 of 2)

1 : gradual decline in strength, soundness, or prosperity or in degree of excellence or perfection the decay of the public school system

2 : a wasting or wearing away : ruin a neighborhood that had fallen into decay

3 obsolete : destruction, death … sullen presage of your own decay. —Shakespeare

4a : 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

5 : a decline in health or vigor mental decay

6 : 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)

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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

While actually observing a Higgs boson is not currently possible, detecting the bits the particle decays into is something the particle accelerator can do. Jason Daley, Smithsonian, "Researchers Find More Evidence for the Higgs Boson," 10 July 2018 Meanwhile, the freeze on new material — including tritium, an element necessary for the North to make advanced atomic bombs as well as the far more powerful hydrogen bombs — would mean that the program would slowly decay. William J. Broad, The Seattle Times, "Bolton says North Korea could disarm in a year," 2 July 2018 And the delays — a mixture of bureaucracy, bad planning and decaying infrastructure — could enable Russia to seize NATO territory in the Baltics while U.S. Army planners were still filling out the 17 forms needed to cross Germany and into Poland. James Hohmann, Washington Post, "The Daily 202: Liberal hostility toward Trump aides could galvanize the GOP base," 25 June 2018 Corruption, decaying oil infrastructure, and a starving workforce have caused production to plummet to the lowest levels in decades. Zeeshan Aleem, Vox, "Why you’ll pay more for gas this Memorial Day weekend," 25 May 2018 Many Baltimore families endure life beside decaying homes. Tim Prudente, baltimoresun.com, "Collapse: The rise and deadly fall of a Baltimore rowhouse," 12 July 2018 Now, after nearly $3 million in renovations since 2015, the once-decaying property has new purpose. Brian Macquarrie, BostonGlobe.com, "At Maine retreat, disabled veterans find sense of belonging," 6 July 2018 The towering walls of dust such as the one that blew through on July 5 are often the result of decaying thunderstorms in other parts of the state. Weldon B. Johnson, azcentral, "Biggest Arizona monsoon threat early in the season? Dust storms," 6 July 2018 Ambulances left decaying corpses outside in sweltering heat. NBC News, "65 dead in Karachi, Pakistan, as temperature tops 111 degrees," 22 May 2018

Recent Examples on the Web: Noun

James helped seal a Game 7 win with a chase-down block of Andre Iguodala, the signature moment of a career that has shown no signs of decay. Tom Withersap, Anchorage Daily News, "LA-Bron: James agrees to 4-year contract with Lakers," 2 July 2018 James helped seal a Game 7 win with a chase-down block of Andre Iguodala, the signature moment of a career that has shown no signs of decay. Tom Withers, Cincinnati.com, "LeBron James agrees to 4-year, $154 million contract with Los Angeles Lakers," 1 July 2018 If Aleppo has now become synonymous with decay, Ms. Helou would do her part to keep its signature recipe alive. New York Times, "The Vast World of Islam, in 300 Recipes," 5 June 2018 Unfortunately, truth decay also spreads because campuses have become safe spaces for dime-store Nietzscheans (there are no facts, only interpretations). George Will, National Review, "The Decay of Truth," 24 Jan. 2018 Saudi conservatives who favored the ban argued that abolishing it would give women too much freedom and lead to social decay. Margherita Stancati And Donna Abdulaziz, WSJ, "Saudi Women Drive Toward More Equality After Ban Is Lifted," 25 June 2018 Old Havana was saved from the wrecking ball but left to poetically decay. Néstor Martí, Smithsonian, "The Man Who Saved Havana," 18 Apr. 2018 To speed cheaper lighting, decay-resistant produce, degradable plastics, and other products to market, DuPont is installing better tools and lab automation. Joseph N. Distefano, Philly.com, "DuPont spends $200M+ to create its future in historic Experimental Station," 18 June 2018 Much like their tournament hosting predecessors Brazil, Russia will attempt to hide the decay and struggle away from the media limelight during the World Cup. SI.com, "PHOTOS: A Look Under the Hood of the 'Real Russia' Behind England's World Cup Group Games," 13 June 2018

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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History and Etymology for decay

Verb

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

Noun

see decay entry 1

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Phrases Related to decay

fall into decay

Statistics for decay

Last Updated

3 Sep 2018

Look-up Popularity

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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 \
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 \

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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Comments on decay

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