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definitions

Tin Pan Alley

noun
  1. the district of a city, especially New York City, where most of the popular music is published.
  2. the composers or publishers of popular music as a group.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for tin pan alley

Tin Pan Alley

noun
  1. a district in a city concerned with the production of popular music, originally a small district in New York
  2. derogatory the strictly commercial side of show business and pop music
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
Word Origin and History for tin pan alley

Tin Pan Alley

n.

"hit song writing business," 1908, from tin pan, slang for "a decrepit piano" (1882). The original one was 28th Street in New York City, home to many music publishing houses.

Online Etymology Dictionary, © 2010 Douglas Harper
tin pan alley in Culture

Tin Pan Alley

A reference to the popular music industry in the United States; the term is not used as much today as it was a generation or two ago.

Note

Tin Pan Alley is often associated with songwriters who are more interested in making money off their songs than in producing high-quality music.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.