mucus

Concise Oxford English Dictionary © 2008 Oxford University Press:
mucus /ˈmjuːkəs/

▶noun

• 1 a slimy substance secreted by the mucous membranes and glands of animals for lubrication, protection, etc.

• 2 mucilage from plants.

– derivatives
mucoid adjective,
mucosity noun,
mucous adjective.

– origin C17: from L.