1

decay

play
verb de·cay \di-ˈkā\

Definition of decay

  1. intransitive verb
  2. 1 :  to decline from a sound or prosperous condition a decaying empire

  3. 2 :  to decrease usually gradually in size, quantity, activity, or force The three voices … decayed and died out upon her ear. — Thomas Hardy

  4. 3 :  to fall into ruin the city's decaying neighborhoods

  5. 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

  6. 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

  7. transitive verb
  8. 1 obsolete :  to cause to decay :  impair infirmity that decays the wise — William Shakespeare

  9. 2 :  to destroy by decomposition wood decayed by bacteria

decayer

noun

Examples of decay in a Sentence

  1. the smell of decaying rubbish

  2. dead plants and leaves decayed by bacteria

  3. She believes that the moral fiber of our society is decaying.

  4. our decaying public school system

  5. The city's neighborhoods are decaying.

Recent Examples of decay from the Web

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.

Origin and Etymology of decay

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

Synonym Discussion of decay

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

2

decay

noun de·cay

Definition of decay

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

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

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

  4. 4a :  rot The material is … resistant to fire, decay and termites … — Jack McClintock; specifically :  aerobic decomposition of proteins chiefly by bacteriab :  the product of decay tooth decay

  5. 5 :  a decline in health or vigor mental decay

  6. 6 :  decrease in quantity, activity, or force: such asa chemistry :  spontaneous decrease in the number of radioactive atoms in radioactive materialb physics :  spontaneous disintegration (as of an atom or a particle)

Examples of decay in a Sentence

  1. the decay of dead plants and leaves

  2. She writes about the moral decay of our society.

  3. the patient's physical and mental decay

  4. The city's neighborhoods are in slow decay.

Recent Examples of decay from the Web

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.

Origin and Etymology of decay

see 1decay



DECAY Defined for English Language Learners

decay

play
verb

Definition of decay for English Language Learners

  • : 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

Definition of decay for English Language Learners

  • : 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 Defined for Kids

1

decay

play
verb de·cay \di-ˈkā\

Definition of decay for Students

decayed

;

decaying

  1. 1 :  to break down or cause to break down slowly by natural processes Fruit decayed on the ground. Sugar decays teeth.

  2. 2 :  to slowly worsen in condition The old theater decayed.


2

decay

play
noun de·cay

Definition of decay for Students

  1. 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. 2 :  a gradual worsening in condition a decay in manners

  3. 3 :  a natural change of a radioactive element into another form of the same element or into a different element


Medical Dictionary

1

decay

play
verb de·cay \di-ˈkā\

Medical Definition of decay

  1. :  to undergo decomposition

  2. transitive verb

  3. :  to destroy by decomposition


2

decay

noun de·cay

Medical Definition of decay

  1. 1a:  rot 1; specifically :  aerobic decomposition of proteins chiefly by bacteriab:  the product of decay

  2. 2a:  spontaneous decrease in the number of radioactive atoms in radioactive materialb:  spontaneous disintegration (as of an atom or a nuclear particle)



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