mole

¹ American  

[mohl] / moʊl /

noun

1. any of various small insectivorous mammals, especially of the family Talpidae, living chiefly underground, and having velvety fur, very small eyes, and strong forefeet.

   I stopped hating the moles in my rose garden when I realized they were eating the Japanese beetle grubs.

2. a spy who becomes part of and works from within the ranks of an enemy governmental staff or intelligence agency.

   There is always a risk that the mole may defect to the enemy.

3. Machinery. a large, powerful machine for boring through earth or rock, used in the construction of tunnels.

   He worked as a mechanic on the mole that created our subway tunnels.

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mole ² American  

[mohl] / moʊl /

noun

1. a small, congenital spot or blemish on the human skin, usually of a dark color, slightly elevated, and sometimes hairy; nevus.

   The pamphlet explains why it's important to monitor changes in a mole's color or shape.

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mole ³ American  

[mohl] / moʊl /

noun

1. a massive structure, especially of stone, set up in the water, as for a breakwater, pier, or causeway: a mole may be topped with pierlike wooden planking, but unlike a typical pier, the mole does not allow water to pass under it.

   Islanders are raising money to restore the mole that once ran to the mainland.

2. an anchorage or harbor protected by such a structure.

   For our small fleet of boats, this mole has been most accommodating.

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mole ⁴ American  

[mohl] / moʊl /

Or mol

noun

Chemistry.

1. the basic unit in the International System of Units (SI), representing the amount of a substance expressed in grams containing as many atoms, molecules, or ions as the number of atoms in 12 grams of carbon-12 (which is Avogadro's number, or 6.022 × 1023 ).

   To express the concentration of the substance in solution, use moles per liter.

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mole ⁵ American  

[mohl] / moʊl /

noun

Pathology, Embryology.

1. molar pregnancy.

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mole ⁶ American  

[moh-ley, maw-le] / ˈmoʊ leɪ, ˈmɔ lɛ /

noun

Mexican Cooking.

1. a spicy sauce typically flavored with dark chocolate, chile peppers, and spices, usually served with turkey or chicken.

   Have you tried making your mole in a slow cooker?

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mole ¹ British  

/ məʊl /

noun

1. any small burrowing mammal, of the family Talpidae, of Europe, Asia, and North and Central America: order Insectivora (insectivores). They have velvety, typically dark fur and forearms specialized for digging

2. any small African burrowing molelike mammal of the family Chrysochloridae, having copper-coloured fur: order Insectivora (insectivores)

3. informal a spy who has infiltrated an organization and, often over a long period, become a trusted member of it

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mole ² British  

/ məʊl /

noun

1. a breakwater

2. a harbour protected by a breakwater

3. a large tunnel excavator for use in soft rock

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mole ³ British  

/ məʊl /

noun

1. pathol a nontechnical name for naevus

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mole ⁴ British  

/ məʊl /

noun

1.  mol.  the basic SI unit of amount of substance; the amount that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12. The entity must be specified and may be an atom, a molecule, an ion, a radical, an electron, a photon, etc

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mole ⁵ British  

/ məʊl /

noun

1. pathol a fleshy growth in the uterus formed by the degeneration of fetal tissues

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mole ⁶ British  

/ ˈməʊleɪ /

noun

1. a spicy Mexican sauce made from chili and chocolate

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mole ¹ Scientific  

/ mōl /

1. A small, usually pigmented, benign growth on the skin.

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mole ² Scientific  

/ mōl /

1. The amount of an element, compound, or other substance that has the same number of basic particles as 12 grams of Carbon-12. The number of particles making up a mole is Avogadro's number. For elements and compounds, the mass of one mole, in grams, is roughly equal to the atomic or molecular weight of the substance. For example, carbon dioxide, CO ₂, has a molecular weight of 44; therefore, one mole of it weighs 44 grams.

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Etymology

Origin of mole¹

First recorded in 1350–1400; Middle English molle; akin to Middle Dutch, Middle Low German mol

Origin of mole²

First recorded before 1000; Middle English; Old English māl; akin to Old High German meil “spot,” Gothic mail “wrinkle”

Origin of mole³

First recorded in 1540–50; from Latin mōlēs “mass, dam, mole”

Origin of mole⁴

First recorded in 1900–05; from German Mol, short for Molekül, the German word for molecule

Origin of mole⁵

First recorded in 1350–1400; Middle English mola, from Latin mola, “millstone, false conception”

Origin of mole⁶

First recorded in 1880–85; from Mexican Spanish, from Nahuatl mōlli “sauce, gravy”; guacamole

Explanation

You may have never seen the fuzzy, pointy-nosed animal called a mole even if you know what a mole is, since it lives underground most of the time. One mole is the mammal with beady little eyes that burrows underground eating earthworms. This mole doesn't need much oxygen to breathe and has big paws for digging tunnels. Another type of mole is basically a large, sometimes raised freckle on the skin; a third is a spy, especially a double agent who pretends to work for one country while sending secret information to another. The burrowing type of mole comes from an obsolete English word, moldwarp, or "earth thrower."

Example Sentences

For decades, mole catchers in the countryside have hung their carcasses on fences to be counted for payment and as evidence of their trapping prowess.

From BBC • Mar. 22, 2026

Chicken mole + frozen roasted corn with cotija + elote chopped salad kit.

From Salon • Feb. 18, 2026

Years later, in her thirties and now a mother, she spotted a mole on her back and immediately feared it might be something serious.

From Science Daily • Dec. 15, 2025

More on health insurance: My insurance company hit me with a $2,000 bill to remove a mole.

From MarketWatch • Dec. 12, 2025

The bottoms were pink and near the left heel there was a tiny brown mole.

From "The Heart is a Lonely Hunter" by Carson McCullers

Related Words

• freckle