noun

• A naevus, a pigmented, slightly raised, and sometimes hairy spot on the skin.
• Any of several small, burrowing insectivores of the family Talpidae; also any of southern African mammals in the family Chrysochloridae (golden moles) and any of several Australian mammals in the family Notoryctidae (marsupial moles), similar to but not closely related to Talpidae moles
• Any of the burrowing rodents also called mole-rats.
• (espionage) An internal spy, a person who involves himself or herself with an enemy organisation, especially an intelligence or governmental organisation, to determine and betray its secrets from within.
• A kind of self-propelled excavator used to form underground drains, or to clear underground pipelines
• A type of underground drain used in farm fields, in which a mole plow creates an unlined channel through clay subsoil.
• (slang, derogatory) A moll, a bitch, a slut.
• (nautical) A massive structure, usually of stone, used as a pier, breakwater or junction between places separated by water.
• (rare) A haven or harbour, protected with such a breakwater.
• (historical) An Ancient Roman mausoleum.
• (chemistry, physics) In the International System of Units, the base unit of amount of substance; the amount of substance of a system which contains exactly 6.02214076×10²³ elementary entities (atoms, ions, molecules, etc.). Symbol: mol. The number of atoms is known as Avogadro’s number. [from 1897]
• A hemorrhagic mass of tissue in the uterus caused by a dead ovum.
• One of several spicy sauces typical of the cuisine of Mexico and neighboring Central America, especially a sauce which contains chocolate and which is used in cooking main dishes, not desserts.
• A river in Surrey, England, tributary to the Thames.
• A river in Devon, England, tributary to the Taw.
• A surname.