Alter \Al"ter\, v. t. [imp. & p. p. Altered; p. pr. & vb. n. Altering.]

[F. alt['e]rer, LL. alterare, fr. L. alter other, alius other. Cf. Else, Other.]

1. To make otherwise; to change in some respect, either partially or wholly; to vary; to modify. ``To alter the king's course.'' ``To alter the condition of a man.'' ``No power in Venice can alter a decree.'' --Shak.

It gilds all objects, but it alters none. --Pope.

My covenant will I not break, nor alter the thing that is gone out of my lips. --Ps. lxxxix. 34.

2. To agitate; to affect mentally. [Obs.]

--Milton.

3. To geld. [Colloq.]

Syn: Change, Alter.

Usage: Change is generic and the stronger term. It may express a loss of identity, or the substitution of one thing in place of another; alter commonly expresses a partial change, or a change in form or details without destroying identity.

Source: Webster's Revised Unabridged Dictionary (1913)