I. di-ˈkā verb
Etymology: Middle English, from Anglo-French decaïr, from Late Latin decadere to fall, sink, from Latin de- + cadere to fall — more at chance
Date: 15th century
intransitive verb
1. : to decline from a sound or prosperous condition
2. : to decrease usually gradually in size, quantity, activity, or force
3. : to fall into ruin
4. : to decline in health, strength, or vigor
5. : to undergo decomposition
decay ing fruit
transitive verb
1. obsolete : to cause to decay : impair
infirmity that decay s the wise — Shakespeare
2. : to destroy by decomposition
• de·cay·er noun
Synonyms:
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
II. noun
Date: 15th century
1. : gradual decline in strength, soundness, or prosperity or in degree of excellence or perfection
2. : a wasting or wearing away : ruin
3. obsolete : destruction , death
4.
a. : rot ; specifically : aerobic decomposition of proteins chiefly by bacteria
b. : the product of decay
5. : a decline in health or vigor
6. : decrease in quantity, activity, or force: as
a. : spontaneous decrease in the number of radioactive atoms in radioactive material
b. : spontaneous disintegration (as of an atom or a particle)