Mole

The word mole when used alone, has several possible meanings in the English language.

• in science, particularly chemistry, the mole is the SI unit for amount of substance. See mole (unit).
• in zoology, a mole is a small burrowing insectivorous mammal. There are also similar-looking but herbivorous rodents called mole rats that enjoy a similar life-style and are commonly called "moles". See mole (animal)
• in cooking, mole is a Mexican sauce made from chilis mixed with spices, unsweetened chocolate, peanuts and many other ingredients. (Note that unlike the other uses on this page, this meaning is derived from the Spanish and is pronounced as two syllables.) See mole (Mexican sauce)
• in medicine, a mole is a small spot of darkened pigment on the skin, which forms where there is a high concentation of melanin. See mole (skin marking)
• in politics, a mole is a spy working under deep-cover, named after the burrowing animal: see Mole (espionage).
• There is a reality television series named after the type of spy: see The Mole.
• In architecture, a massive structure, usually of stone, used as pier, breakwater or junction between places separated by water: see Mole (architecture).
• In engineering, a mole machine is a vehicle designed to travel underground by boring a tunnel.