Mole (?), n. [AS. māl; akin to OHG. meil, Goth. mail Cf. Mail a spot.] 1. A spot; a stain; a mark which discolors or disfigures. [Obs.] Piers Plowman.
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2. A spot, mark, or small permanent protuberance on the human body; esp., a spot which is dark-colored, from which commonly issue one or more hairs.
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Mole, n. [F. môle, L. moles. Cf. Demolish, Emolument, Molest.] A mound or massive work formed of masonry or large stones, etc., laid in the sea, often extended either in a right line or an arc of a circle before a port which it serves to defend from the violence of the waves, thus protecting ships in a harbor; also, sometimes, the harbor itself. Brande & C.
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mole n. A quantity of a substance equal to the molecular weight of a substance expressed in grams; a gram molecule; the basic unit of amount of substance adopted under the System International d'Unites; as, he added two moles of sodium chloride to the medium.
Syn. -- gram molecule, mol.
[WordNet 1.5]