A device-to-device parallel bus standard for computers, abbreviated
SCSI.
Typically, each peripheral or internal device on the bus is assigned a 0 to 7 identifier. The host adapter that bridges the SCSI bus to the system bus is also assigned an identifier.
Many updates to the concept exist, Fast Wide SCSI-2, etc.
Some pronounce it 'sexy', most prefer to say 'scuzzy'.