A USB on a computer is a place where you can attach another piece of equipment, for example a printer. USB is an abbreviation for 'Universal Serial Bus'.
[computing]
The device plugs into one of the laptop's USB ports.
USB in British English
abbreviation for
Universal Serial Bus: a standard for connection sockets on computers and other electronic equipment
USB in American English
Universal Serial Bus
used to designate a kind of standard interface for connecting peripherals to a computer
Examples of 'USB' in a sentence
USB
He returned to the study and plugged the scanner into his laptop's USB port.