decease (v.) Copy link Outline 1. dēmŏrior, mortuus, 3 (esp. with ref. to a successor)2. dēcēdo, excēdo • decease (v.): 1. dēmŏrior, mortuus, 3 (esp. with ref. to a successor): one of the old senators having d.d, cum esset ex veterum numero quidam senator demortuus, Cic.: into the room of the d.d, in locum demortui, id. 2. dēcēdo, excēdo: v. to die.