De*cay" (?), v. i. [imp. & p. p. Decayed (?); p. pr. & vb. n. Decaying.] [OF. decaeir, dechaer, decheoir, F. d├ęchoir, to decline, fall, become less; L. de- + cadere to fall. See Chance.] 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; as, a tree decays; fortunes decay; hopes decay.

Ill fares the land, to hastening ills a prey,
Where wealth accumulates and men decay.

De*cay", n. 1. Gradual failure of health, strength, soundness, prosperity, or of any species of excellence or perfection; tendency toward dissolution or extinction; corruption; rottenness; decline; deterioration; as, the decay of the body; the decay of virtue; the decay of the Roman empire; a castle in decay.

Perhaps my God, though he be far before,
May turn, and take me by the hand, and more -
May strengthen my decays.

His [Johnson's] failure was not to be ascribed to intellectual decay.

Which has caused the decay of the consonants to follow somewhat different laws.
James Byrne.

2. Destruction; death. [Obs.] Spenser.

3. Cause of decay. [R.]

He that plots to be the only figure among ciphers, is the decay of the whole age.

Syn. -- Decline; consumption. See Decline.

De*cay", v. t. 1. To cause to decay; to impair. [R.]

Infirmity, that decays the wise.

2. To destroy. [Obs.] Shak.