Member of a Roman Catholic monastic order founded by St. Bruno of Cologne (c. 1030–1101) in 1084 in the Chartreuse valley of southeastern France. Members of the Order of Carthusians pray, study, eat, and sleep alone but gather in church for morning mass, vespers, and the night office. They dine together on Sundays and major holidays and walk together once a week. They wear hair shirts, abstain from eating meat, and consume only bread and water on Fridays and fast days. At the motherhouse, or Grande Chartreuse (today in Voiron, Isère), the monks distill the liqueur that bears the house's name. Carthusian nuns are also strictly cloistered and contemplative.