(1) A receptacle for a printed circuit board. Synonymous with "socket." See
expansion card and
plugs and sockets.
(2) A receptacle for inserting and removing a disk or tape cartridge. Removable storage was popular in the 1990s. See
removable drive.
(3) In communications, a narrow band of frequencies. See
time slot.
(4) Reserved space for temporary or permanent storage of instructions, data or codes. See
buffer.