regression

noun

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