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definitions

open-reel tape

[oh-puh n-reel]
noun
  1. audiotape, usually 1/4 inch (64 mm) wide, wound on a single reel and requiring a separate take-up reel for playing or recording.

Origin of open-reel tape

First recorded in 1965–70
Also called reel-to-reel tape.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018