(n) :
a membrane which secretes mucus. It forms the lining of various body passages that communicate with the air, such as the respiratory, genitourinary, and alimentary tracts including the mouth, nasal passages, vagina and urethra
(n) :
a membrane which secretes mucus. It forms the lining of various body passages that communicate with the air, such as the respiratory, genitourinary, and alimentary tracts including the mouth, nasal passages, vagina and urethra