regress

Etymology

(verb) From Latin regressus, past participle of regredior (“to go back”), from re- (“back”) + gradior (“to go”).

noun

1. The act of passing back; passage back; return; retrogression.
   Its bearing on the progress or regress of man is not an inconsiderable question. 1886, Frederic Harrison, The Choice of Books
2. The power or liberty of passing back.
3. (property law) The right of a person (such as a lessee) to return to a property.

verb

1. (intransitive) To move backwards to an earlier stage; to devolve.
   1. (psychology) To re-develop behavior one had previously grown out of, particularly a behavior left behind in childhood.
      Your nightmares stopped when you were eight years old, but after the house burned down, you regressed.
2. (intransitive, astronomy) To move in the retrograde direction.
3. (intransitive, medicine) To reduce in severity or size (as of a tumor), without reaching total remission.
4. (transitive, statistics) To perform a regression on an explanatory variable.
   When we regress Y on X, we use the values of variable X to predict those of Y.
5. (transitive) To interrogate a person in a state of trance about forgotten elements of their past.
   They regressed me, putting me under hypnosis. Then, through the hypnosis, they found out that our car was abducted right off the road and into a craft. 2018, Michael Brein, Rosemary Ellen Guiley, The Road to Strange: UFOs, Aliens and High Strangeness