(derogatory, politics, rare) The politics of the regressive left.

(software engineering) Testing a program after a modification to ensure that areas that should not be affected by the update behave as they did in previous versions.

(phonetics, phonology) An assimilation whereby a sound becomes more like the following sound.

plural of regressive assimilation

Mental reversion to a younger age, used in therapy, as a coping mechanism, or as a manifestation of a psychiatric issue.

(statistics) A linear equation for deriving a single predicted value from one or more known explanatory values.

(psychology) A period of days or weeks during the first two years of life characterized by a change in an infant's sleep patterns, leading to irregularities such as increased awakenings and fussiness.

(statistics, derogatory) A statistical regression which uses many possible independent variables to attempt to explain variance in a dependent variable.

Alternative form of regression to the mean.