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definitions

piano roll

noun
  1. a roll of paper containing perforations such that air passing through them actuates the keys of a player piano.

Origin of piano roll

First recorded in 1925–30
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for piano roll

piano roll

noun
  1. a perforated roll of paper actuating the playing mechanism of a PianolaAlso called: music roll
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