pro·lapse
noun/ˈprəʊlæps/
/ˈprəʊlæps/
(medical)- a condition in which an organ of the body has slipped forward or down from its normal position
（身体器官的）脱垂，下垂，脱出 Word Originmid 18th cent.: from Latin prolaps- ‘slipped forward’, from the verb prolabi, from pro- ‘forward, down’ + labi ‘to slip’.