Watrapisti (ufupisho wa jina la shirika lao ni OCSO, Ordo Cistercensium Strictae Observantiae) ni wamonaki wa Kanisa Katoliki wanaofuata kikamilifu urekebisho wa umonaki wa Kibenedikto ambao ulianza Citeaux (leo nchini Ufaransa) tarehe 21 Machi 1098 ukaenea haraka kila mahali katika karne ya 12, hasa kutokana na mvuto wa mwanashirika Bernardo wa Clairvaux. Jina linatokana na monasteri ya La Trappe, Normandy, ambapo mwaka 1664 Armand Jean le Bouthillier de Rancé alianzisha tapo lenye msimamo mkali zaidi kuhusu kazi za mikono, kimya, kujinyima chakula, kujitenga na ulimwengu na kukataa masomo mengi. Kwa sasa (2018) wana monasteri 168 katika mabara yote. Wasitoo wengine wanaunda shirikisho la O.Cist.. Plouvier, M. and Saint-Denis, A. (eds.), 1998: Pour une histoire monumentale de Cîteaux, 1098-1998 (Commentarii cistercienses. Studia et documenta, 8), Cîteaux. Wikimedia Commons ina media kuhusu: Watrapisti Official website Trappists in the United States Memoir of Father Vincent de Paul, religious of La Trappe at Project Gutenberg Official site (in French) History of Cîteaux Abbey (in French) Photo Archived 16 Oktoba 2005 at the Wayback Machine.