Spool can mean one of the following: Spool, an unflanged plastic cylindrical hub on which magnetic tape is wound in a compact cassette. Spool, a usually low-flanged or unflanged cylinder on which thread, wire, cable, paper, or film is wound for distribution and use. Bobbin, a cylinder or reel on which a quantity of thread, yarn or wire is wound for use in a particular machine or device. Spooling, a physical or metaphorical data storage device in computing. Spool, a shaft of a gas turbine en… (More on Spool)