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mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

nucleus, in biology

(Encyclopedia)nucleus: see cell, in biology.

nucleus, in physics

(Encyclopedia)nucleus, in physics, the extremely dense central core of an atom. Following the discovery of radioactivity by A. H. Becquerel in 1896, Ernest Rutherford identified two types of radiation given off b...

nun, in religion

(Encyclopedia)nun: see monasticism.

nut, in botany

(Encyclopedia)nut, in botany, a dry one-seeded fruit which is indehiscent (i.e., does not split open along a definite seam at maturity). Among the true nuts are the acorn, chestnut, and hazelnut. Commonly the word ...

nymph, in zoology

(Encyclopedia)nymph, in zoology: see insect.

note, in business

(Encyclopedia)note, in business: see promissory note. ...

note, in music

(Encyclopedia)note, in musical notation, symbol placed on or between the lines of a staff to indicate the pitch and the relative duration of the tone to be produced by voice or instrument. The largest note value in...

nimbus, in art

(Encyclopedia)nimbus nĭmˈbəs [key], in art, the luminous disk or circle or other indication of light around the head of a sacred personage. It was used in Buddhist and other Asian art and by the early Greeks and...

nimbus, in meteorology

(Encyclopedia)nimbus, in meteorology, low, dark, formless cloud covering the entire sky, from which rain or snow is steadily falling. The term is usually applied to any cloud from which rain descends. Modifications...