wave number

American  

noun

1. the number of waves in one centimeter of light in a given wavelength; the reciprocal of the wavelength.

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wave number British  

noun

1.  ν.   σ.  physics the reciprocal of the wavelength of a wave

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wave number Scientific  

1. The number of wave cycles per unit distance for a wave of a given wavelength.

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Etymology

Origin of wave number

First recorded in 1900–05