An Etymological Dictionary of the German Language/Annotated/Sigrist
Sigrist, masculine, ‘sexton, sacristan,’ from the equivalent Middle High German sigriste, Old High German (also Old Low German) sigristo; borrowed during the Old High German period contemporaneously with Priester, predigen, and especially with Küster and Meßner, from Latin sacrista, whose Middle Latin variant segrista(nus) leads to Old French segretain (in Modern French sacristain, Italian sagrestano, English sexton).