from The American Heritage® Dictionary of the English Language, 5th Edition.

  • intransitive verb Biology To break down into component parts; rot.
  • intransitive verb Physics To disintegrate in a process of radioactive decay or particle decay.
  • intransitive verb Electronics To decrease gradually in magnitude. Used of voltage or current.
  • intransitive verb Aerospace To decrease in orbit. Used of an artificial satellite.
  • intransitive verb To fall into ruin.
  • intransitive verb To decline in health or vigor; waste away.
  • intransitive verb To decline from a state of normality, excellence, or prosperity; deteriorate.
  • intransitive verb To cause to decay.
  • noun The destruction or decomposition of organic matter as a result of bacterial or fungal action; rot.
  • noun Rotted matter.
  • noun Aerospace The decrease in orbital altitude of an artificial satellite as a result of conditions such as atmospheric drag.
  • noun A gradual deterioration to an inferior state.
  • noun A falling into ruin.

from The Century Dictionary.

  • To pass gradually from a sound or perfect state to a less perfect state, or toward weakness or dissolution; fall into an inferior condition or state; specifically, become decomposed or corrupted; rot.
  • Synonyms Putrefy, Corrupt, etc. See rot.
  • To cause to become unsound or impaired; cause to deteriorate; impair; bring to a worse state.
  • noun Gradual loss of soundness or perfection; a falling by degrees into an impaired condition or state; impairment in general; loss of strength, health, intellect, etc.
  • noun Specifically Decomposition; putrefaction; rot.
  • noun 3. Death; dissolution.
  • noun . A disease; especially, consumption.
  • noun . A cause of decay.
  • noun Loss of fortune or property; misfortune; ruin : applied to persons.
  • noun . plural Ruins.
  • noun Synonyms Decline, decadence, deterioration, degeneracy, withering.

from the GNU version of the Collaborative International Dictionary of English.

  • transitive verb rare To cause to decay; to impair.
  • transitive verb obsolete To destroy.
  • intransitive verb To pass gradually from a sound, prosperous, or perfect state, to one of imperfection, adversity, or dissolution; to waste away; to decline; to fail; to become weak, corrupt, or disintegrated; to rot; to perish
  • noun Gradual failure of health, strength, soundness, prosperity, or of any species of excellence or perfection; tendency toward dissolution or extinction; corruption; rottenness; decline; deterioration
  • noun obsolete Destruction; death.
  • noun rare Cause of decay.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun The process or result of being gradually decomposed.
  • noun A deterioration of condition.
  • verb intransitive To deteriorate, to get worse, to lose strength or health, to decline in quality.
  • verb intransitive To rot, to go bad.
  • verb intransitive, transitive, physics, chemistry To change by undergoing fission, by emitting radiation, or by capturing or losing one or more electrons.
  • verb intransitive, transitive, physics To undergo optical decay, that is, to relax to a less excited state, usually by emitting a photon or phonon.
  • verb transitive To cause to rot or deteriorate.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun the process of gradually becoming inferior
  • noun a gradual decrease; as of stored charge or current
  • noun the spontaneous disintegration of a radioactive substance along with the emission of ionizing radiation
  • verb undergo decay or decomposition
  • verb lose a stored charge, magnetic flux, or current
  • verb fall into decay or ruin
  • noun the organic phenomenon of rotting
  • noun an inferior state resulting from the process of decaying


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English decayen, from Old French decair, from Vulgar Latin *dēcadere : Latin dē-, de- + Latin cadere, to fall; see kad- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Old French decair ("to fall away, decay, decline"), from Medieval Latin *decadere, restored form of Latin decidere ("to fall away, fail, sink, perish"), from de ("down") + cadere ("to fall"); compare decadent and decadence.


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  • I agree. Good call.

    November 27, 2007

  • To declare your undismay,

    Put de O before de K.

    November 27, 2007

  • Sounds like the letters D K.

    October 28, 2009

  • And also the Greek δίκη, which means Justice.

    October 29, 2009