regression

Short definition from Wiktionary

Noun

1. 1
   An action of regressing, a return to a previous state.
2. 2
   An action of travelling mentally back in time.
3. 3
   A psychotherapeutic method whereby healing is facilitated by inducing the patient to act out behaviour typical of an earlier developmental stage.
4. 4
   An analytic method to measure the association of one or more independent variables with a dependent variable.
5. 5
   An equation using specified and associated data for two or more variables such that one variable can be estimated from the remaining variable(s).
6. 6
   The reappearance of a bug in a piece of software that had previously been fixed.
7. 7
   The diminishing of a cellular mass like a tumor, or of an organ size.
8. 8
   The making an exercise less straining to perform by manipulating the details of its performance like loaded weight, range of motion, angle, speed.