Wiktionary
tape library
n. A device holding tape drives for storage purposes.
Wikipedia
Tape library
In computer storage, a tape library, sometimes called a tape silo, tape robot or tape jukebox, is a storage device which contains one or more tape drives, a number of slots to hold tape cartridges, a barcode reader to identify tape cartridges and an automated method for loading tapes (a robot).
One of the earliest examples was the IBM 3850 Mass Storage System (MSS), announced in 1974.