1a return to a former or less developed state:it is easy to blame unrest on economic regression
a return to an earlier stage of life or a supposed previous life, especially through hypnosis:the details recalled by Carol during the regression [as modifier]:regression therapy [count noun]:a past-life regression
a lessening of the severity of a disease or its symptoms:there was 46.7 per cent complete regression in the placebo group
2 Statistics a measure of the relation between the mean value of one variable (e.g. output) and corresponding values of other variables (e.g. time and cost).
