Regressive \Re*gress"ive\ (r?*gr?s"?v), a. [Cf. F. r['e]gressif.]

1. Passing back; returning.

2. Characterized by retrogression; retrogressive.

Regressive metamorphism.
   (a) (Biol.) See Retrogression.
   (b) (Physiol.) See Katabolism.

Source: Webster's Revised Unabridged Dictionary (1913)