serosa
noun
se·ro·sa sə-ˈrō-zə 
: a usually enclosing serous membrane
serosal
sə-ˈrō-zəl
adjective 
Word History
Etymology
borrowed from New Latin serōsa, short for membrāna serōsa "serous membrane" — more at serous
First Known Use
circa 1890, in the meaning defined above
Medical Definition
serosa
noun
se·ro·sa sə-ˈrō-zə
plural serosas also serosae -zē
: a usually enclosing serous membrane
the peritoneal serosa