Re*demp"tor*ist (-t?r*?st), n. [F. rédemptoriste, fr. L. redemptor redeemer, from redinere. See Redeem.] (R.C.Ch.) One of the Congregation of the Most Holy Redeemer, founded in Naples in 1732 by St. Alphonsus Maria de Liquori. It was introduced onto the United States in 1832 at Detroit. The Fathers of the Congregation devote themselves to preaching to the neglected, esp. in missions and retreats, and are forbidden by their rule to engage in the instruction of youth.