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subwoofer

[suhb-woo f-er]
noun
  1. a loudspeaker component designed to reproduce only extremely low bass frequencies, generally below 125 Hz.

Origin of subwoofer

sub- + woofer
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for subwoofer

subwoofer

noun
  1. a loudspeaker for reproducing very low frequencies only
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