noun
( anatomy ) a thin layer of skin that covers the inside of the nose and mouth and the outside of other organs in the body, producing mucus to prevent these parts from becoming dry
noun
( anatomy ) a thin layer of skin that covers the inside of the nose and mouth and the outside of other organs in the body, producing mucus to prevent these parts from becoming dry
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005