mu·cus /ˈmjukəs/ 名詞
1. Physiol. A viscid fluid secreted by mucous membranes, which it serves to moisten and protect. It covers the lining membranes of all the cavities which open externally, such as those of the mouth, nose, lungs, intestinal canal, urinary passages, etc.
2. Physiol. Any other animal fluid of a viscid quality, as the synovial fluid, which lubricates the cavities of the joints; -- improperly so used.
3. Bot. A gelatinous or slimy substance found in certain algae and other plants.
n : protective secretion of the mucous membranes; in the gut it
lubricates the passage of food and protects the
epithelial cells; in the nose and throat and lungs it can
make it difficult for bacteria to penetrate the body
through the epithelium [syn: mucous secretion]