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side band

or side·band

noun Radio.
  1. the band of frequencies at the sides of the carrier frequency of a modulated signal.

Origin of side band

First recorded in 1795–1805
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for sideband

sideband

noun
  1. the frequency band either above (upper sideband) or below (lower sideband) the carrier frequency, within which fall the spectral components produced by modulation of a carrier waveSee also single sideband transmission
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