The Free On-line Dictionary of Computing (19 January 2023):

AT Attachment Packet Interface
ATAPI

    (ATAPI) Part of the EIDE interface that provides
   additional commands to control a CD-ROM drive or magnetic
   tape.

   [Winn L. Rosch "The Winn L. Rosch Hardware Bible"
   (Third Edition), Sams Publishing, 1994].

   (1998-11-01)