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wave number

American  

noun

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


wave number British  

noun

  1.  ν.   σphysics the reciprocal of the wavelength of a wave

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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


Etymology

Origin of wave number

First recorded in 1900–05