de|cay

de|cay «dih KAY», verb, noun.

–v.i.

1. to become rotten; rot: »

The old apples got soft and decayed. Her teeth decayed because she ate too many sweets. The beams of the old house had decayed and fallen in.

2. to grow less in power, strength, wealth, or beauty: »

Many nations have grown great and then decayed. The power of the Roman Empire was decaying at the time of Nero.

SYNONYM(S): deteriorate, decline.

3. to decrease in number, volume, intensity, or power.

4. Physics. (of radioactive substances) to disintegrate by the emission of various types of rays: »

This radioactivity “decays,” or decreases, rapidly but the fission products can contaminate (Hanson W. Baldwin).

5. Aerospace. (of an orbiting earth satellite) to slow down because of atmospheric friction.

–v.t.

to cause to decay: »

Too many sweets may decay the teeth.

–n.

1. a rotting: »

tooth decay. The decay of the tree trunk proceeded so rapidly the tree fell over in a year. If bacterial decay did not occur, the life activities of plants and animals would of necessity come to a standstill (Fred W. Emerson).

SYNONYM(S): putrefaction.

2. a decayed condition: »

Round the decay of that colossal wreck (Shelley).

3. a loss of power, strength, wealth, or beauty: »

The decay of the old lady's health and vigor was very gradual. Age is not all decay (George MacDonald).

SYNONYM(S): deterioration, decline.

4. a decrease in number, volume, intensity, or power.

5. Physics. the loss in quantity of a radioactive substance through disintegration of its component nuclei, as by the emission of alpha particles or beta particles.

6. Aerospace. reduction in speed of an orbiting earth satellite, caused by atmospheric friction.

7. Obsolete. a) destruction; ruin. b) consumption; phthisis.

╂[< Old French decair < de- down (< Latin dē-) + cair < Latin cadere to fall]

–de|cay´er, noun.

Synonym Study intransitive verb. 1 Decay, rot, decompose mean to change from a good or healthy condition to a bad one. Decay emphasizes the idea of changing little by little through natural processes: »

Some diseases cause the bones to decay.

Rot, more emphatic, emphasizes the idea of spoiling and applies especially to plant and animal matter: »

The fruit rotted on the vines.

Decompose emphasizes the idea of breaking down into original parts, by natural or chemical processes: »

Bodies decompose after death.