syn·o·vi·al
adjective/saɪˈnəʊviəl/, /sɪˈnəʊviəl/
/sɪˈnəʊviəl/
(biology)- (of a part of the body ) having a membrane (= a piece of very thin skin) containing liquid between the bones, which allows the joint to move freely
（含）滑膜的 Word Originmid 18th cent.: from modern Latin synovia, probably formed arbitrarily by Paracelsus (c. 1493-1541), the Swiss physician.