Definition of "decay"

The process or result of being gradually decomposed.  quotations  examples

A deterioration of condition; loss of status or fortune.  examples

(obsolete) Overthrow, downfall, ruin.  quotations

(programming) The situation, in programming languages such as C, where an array loses its type and dimensions and is reduced to a pointer, for example by passing it to a function.  examples

(intransitive) To deteriorate, to get worse, to lose strength or health, to decline in quality.

1. (intransitive, electronics, of storage media or the data on them) To undergo bit rot, that is, gradual degradation.  examples

2. (intransitive, computing, of software) To undergo software rot, that is, to fail to be updated in a changing environment, so as to eventually become legacy or obsolete.  examples

3. (intransitive, physics, of a satellite's orbit) To undergo prolonged reduction in altitude (above the orbited body).  quotations  examples

   Quotations

   • Damaged on lift-off, Skylab was left in orbit until its orbit decayed.

     2009, Francis Lyall, Paul B. Larsen, Space Law: A Treatise, page 120

(intransitive, of organic material) To rot, to go bad.  examples

(intransitive, transitive, physics, chemistry, of an unstable atom) To change by undergoing fission, by emitting radiation, or by capturing or losing one or more electrons; to undergo radioactive decay.  quotations  examples

(intransitive, transitive, physics, of a quantum system) To undergo optical decay, that is, to relax to a less excited state, usually by emitting a photon or phonon.  examples

(intransitive, aviation) Loss of airspeed due to drag.  examples

(transitive) To cause to rot or deteriorate.  quotations  examples

(programming, intransitive) Of an array: to lose its type and dimensions and be reduced to a pointer, for example when passed to a function.  examples