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 For the next 40 years, the cottages — forerunners of the California Craftsman-style bungalow — were left to decay, becoming notorious eyesores in the picturesque spot. San Diego Union-Tribune, "Plans being made for La Jolla site after fire extensively damages 126-year-old cottage," 8 Nov. 2020 Leaving the top and stem intact slows decay and helps make your pumpkin look professional. Sarah Martens, Better Homes & Gardens, "Learn How to Etch a Pumpkin for Halloween," 15 Oct. 2020 Their faces begin to decay and their eyes are swallowed up. Shannon Carlin, refinery29.com, "The Haunting of Bly Manor," 13 Oct. 2020 Without logging, the highly combustible oil in trees' needles dissipates within two years of a tree being killed by drought or bark beetles, while the needles themselves decay into dirt. Mark Olalde, USA TODAY, "Creek Fire ignites fire management debate on 102 million trees killed by beetles, drought," 16 Sep. 2020 In the end, Emily decided to forgo embalming and have her body kept on ice for a home vigil before being placed in the ground to decay. Star Tribune, "When cancer hijacked a new mother's happily ever after, she planned a death as unconventional as her life. A year later, her husband is the father he never expected to be, carrying on her legacy.," 11 Oct. 2020 Their faces begin to decay and their eyes are swallowed up. Shannon Carlin, refinery29.com, "The Haunting of Bly Manor," 9 Oct. 2020 However, most mulch products are made from wood byproducts, and dead wood will always eventually decay in the presence of moisture. Beth Botts, chicagotribune.com, "Landscape fabric can do more harm than good under mulch in your garden. Here’s a better, cheaper alternative to try.," 26 Sep. 2020 These fungi decay organic debris in the lawn — grass clippings and dead leaves would otherwise accumulate and choke out the grass. Dan Gill, NOLA.com, "Dan Gill's mailbag: Get rid of dallisgrass while it's young, but mushrooms aren't so bad," 23 Sep. 2020 Recent Examples on the Web: Noun Composting is a technique where humans speed up the decay process. Dan Gill, NOLA.com, "Turn icky leftovers and trimmings into compost, something that's good for your garden," 18 Nov. 2020 Jack O' Lantern mushrooms can be a pathogenic wood decay mushroom on deciduous trees. Ellen Nibali, baltimoresun.com, "Garden Q&A: On glowing mushrooms and planting trees amid cicada hatch," 29 Oct. 2020 Violent death and extinction are a constant presence, as is environmental decay, which such series have begun to invoke with increasing urgency. Carrie Battan, The New Yorker, "The Unsettling Anti-Entertainment of “A World of Calm”," 27 Oct. 2020 Careful brushing not only helps stop tooth decay but can also stop you from grossing out your family. Jason Bittel, Washington Post, "How do braces straighten your teeth?," 16 Oct. 2020 These include ganoderma applanatum, large bracket mushrooms that cause wood decay; armillaria, a fungal root-rot; phytophthora, a destructive water mold and hypoxylon, a fast-growing fungal canker. Juhi Varma, Houston Chronicle, "Houston arborist discusses tree care tips during storms, hurricanes," 28 Sep. 2020 In one such experiment, the lifetime of muon decay verifies the existence of time dilation. Ronald C. Lasky, Scientific American, "Does Time Tick at the Same Rate for Everyone?," 24 Oct. 2014 There is a serious decay fungus that has developed within the internal tissues of your tree. Neil Sperry, ExpressNews.com, "Neil Sperry: Amaryllis likely to grow, overwinter better in pots," 12 Nov. 2020 Physicists think the trick to spying them is speeding up their otherwise glacial decay into photons, which are relatively easy to spot. Ryan Bradley, Popular Science, "Glimpse the gold mine where scientists are searching for dark matter," 27 Oct. 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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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

15 Nov 2020

Cite this Entry

“Decay.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/decay. Accessed 4 Dec. 2020.

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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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Comments on decay

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