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see birthmarkbirthmark,
pigmented maldevelopment of the skin that varies in size, either present at birth or developing later. Birthmarks may appear as moles (melanocytic nevi) that vary in color from light brown to blue, and are either flat or raised above the surface of the skin.
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in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weightgram-molecular weight,
amount of a molecular substance whose weight, in grams, is numerically equal to the molecular weight of that substance. For example, one gram-molecular weight of molecular oxygen, O2
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 of any molecular substance contains exactly one mole of molecules. The term mole is often used in place of gram-molecular weight; e.g., one speaks of 18 grams of water as one mole of water rather than as one gram-molecular weight of water. The mole is a unit in the International System of UnitsInternational System of Units,
officially called the Système International d'Unités, or SI, system of units adopted by the 11th General Conference on Weights and Measures (1960). It is based on the metric system.
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in zoology, common name for the small, burrowing, insectivorous mammals of the family Talpidae, found throughout the temperate Northern Hemisphere. Moles are trapped as pests, although they probably do less damage than the animals they destroy, and for their fur, which is highly valued.

Typical moles have rounded bodies about 6 in. (15.2 cm) long covered with soft black or gray fur; they have pointed muzzles and lack external ears. They have acute hearing and a highly developed sense of touch at the ends of their noses and tails; their tiny eyes, covered with skin or buried in fur, are sensitive to changes in light level but provide little visual acuity. Moles have short, powerful legs and extremely broad front feet, which are used as shovels and are equipped with enormous digging claws. They can move backwards almost as rapidly as forwards, and most are good swimmers.

Moles tunnel just below the surface of the ground, where they hunt for food. Their tunnels make ridges and mounds in fields, gardens, and lawns; quarters for living, nesting, and wintering are in deeper burrows. A single mole can dig about 20 yd (18 m) of tunnel in a day. Moles are voracious eaters, consuming about half their own weight daily. Their diet consists mainly of earthworms and insects, but also includes small mammals such as mice; one mole may even kill and eat another when they happen to meet. They are solitary most of the year, but during the breeding season they travel in pairs. The litter, born in the spring after four weeks of gestation, consists of two to seven young.

Typical species include the common European mole, Talpa europaea, and the eastern, or garden, mole of North America, Scalopus aquaticus, both about 6 in. (15.2 cm) long with a 1-in. (2.54-cm) tail. The largest moles are the western moles of North America, genus Scapanus, which may reach a length of 9 in. (22.9 cm). The smallest New World mole is the 3-in. (7.6-cm) shrew mole, Neurotrichus gibbsii, of the Pacific Northwest, which resembles a shrew and prefers a forest habitat, spending much time above ground. The strangest-looking of the family is the star-nosed mole, Condylura cristata, of northeastern North America, which has a ring of mobile fleshy protuberances around its snout. This mole is a good diver and leads a semiaquatic life; apparently it uses the protuberances to pick up sounds in the water.

There are no true moles in the Southern Hemisphere. The golden moles of S Africa are members of the insectivorous family Chrysochloridae; they are burrowing animals with bright golden fur. There are burrowing rodents in Africa called strand moles and burrowing marsupials in Australia called marsupial moles. True moles are classified in the phylum ChordataChordata
, phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal skeletal support at some stage of their development. Most chordates are vertebrates (animals with backbones), but the phylum also includes some small marine invertebrate animals.
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, subphylum Vertebrata, class Mammalia, order Soricomorpha, family Talpidae.


See study by K. Mellanby (1973).

The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a quantitative unit of matter characterizing the number of identical structural elements (atoms, molecules, ions, and other particles or their specific groups) in a physical system. A mole is equal to the amount of matter that contains the same number of particles as the number of atoms in an exactly 0.012-kg sample of a nuclide of 12C (Avogadro’s number, 6.022 X 1023). The Russian symbol for mole is mol; the international symbol is mol.

By a decision of the Fourteenth General Conference on Weights and Measures in 1971, the mole was adopted as the seventh fundamental unit in the International System of Units. The multiple unit is the kilomole (1 kmol = 103 moles).

The mole is used in the derivation of molar quantities such as the molar weight (kg/mol), molar volume (m3 /mol), molar internal energy (J/mol), molar heat capacity (J/[mol.°K]), and molar concentration (mol/m3).



a breakwater that protects the water area of a port from waves and that abuts the shore at one end; a mole may also serve at the same time as a place for hawsers and loading equipment.

In ports located on the open sea, two converging or parallel moles are constructed with gates between them (double, or paired, moles). If the port is situated in a bay whose shore partly protects the water area from wind and waves, the water area is usually bounded by one mole. The design and type of mole is mainly determined by the hydrologic and geologic conditions of the region in which the port is located. Moles may be of the sloping type (built of rubble made of stone or concrete blocks), the vertical type (walls erected with masonry, concrete, or rein-forced-concrete blocks), or a combination of both types. The top part of the mole (the part pushing out into the sea) is made 1-1.5 m higher than the rest and has a signal light or beacon mounted on it.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

What does it mean when you dream about a mole?

A blemish on the body suggests that something is marring or interfering with the dreamer’s personal esteem or that the dreamer is unable to obtain the desired esteem of others. A mole can also refer to a ground-dwelling rodent. It may represent thoughts arising from the dark depths of one’s subconscious mind, unearthing hidden agendas that need to be brought to light.

The Dream Encyclopedia, Second Edition © 2009 Visible Ink Press®. All rights reserved.


An amount of substance of a system which contains as many elementary units as there are atoms of carbon in 0.012 kilogram of the pure nuclide carbon-12; the elementary unit must be specified and may be an atom, molecule, ion, electron, photon, or even a specified group of such units. Symbolized mol.
(civil engineering)
A breakwater or berthing facility, extending from shore to deep water, with a core of stone or earth.
(mechanical engineering)
A mechanical tunnel excavator.
A mass formed in the uterus by the maldevelopment of all or part of the embryo or of the placenta and membranes.
A fleshy, pigmented nevus.
(vertebrate zoology)
Any of 19 species of insectivorous mammals composing the family Talpidae; the body is stout and cylindrical, with a short neck, small or vestigial eyes and ears, a long naked muzzle, and forelimbs adapted for digging.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


said to lack eyes. [Medieval Animal Symbolism: White, 95–96]
Allusions—Cultural, Literary, Biblical, and Historical: A Thematic Dictionary. Copyright 2008 The Gale Group, Inc. All rights reserved.


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. golden mole 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


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.


1. a breakwater
2. a harbour protected by a breakwater
3. a large tunnel excavator for use in soft rock


Pathol a fleshy growth in the uterus formed by the degeneration of fetal tissues
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


A unit of measurement of molecular weight. Part of the SI system of measurement, one mole (mol) is equal to 6.02257 X 10 to the 23rd molecules. See SI units.
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