Definition of: regress

(rē′gres) noun
1. Passage back; return; also, the power or right of passing back or returning.
2. Retrogression.
—v.i. (ri·gres′)
1. To go back; move backward; return.
2. Astron. To move in a direction opposite to that of the general motion of the heavenly bodies, as the moon's nodes.
3. Stat. To return to the mean value of a series of observations. [<L regressus, pp. of regredi go back <re- back + gradi walk]
—re·gres′sor noun