Late Middle English (in an earlier sense). From Middle French refrenation action of restraining, restraint and its etymon classical Latin refrēnātiōn-, refrēnātiō act or faculty of restraining, control, restraint, in post-classical Latin also (in medicine) action of reducing or restraining abnormal humours, (in astrology) prevention of a conjunction of two planets by the retrogression of one of them from refrēnāt-, past participial stem of refrēnāre + -iō; compare -ation.