A trackball is a ball on some computers that you turn in order to move the cursor.
[computing]
trackball in British English
(ˈtrækˌbɔːl) or trackerball (ˈtrækəˌbɔːl)
noun
computing
a device consisting of a small ball, mounted in a cup, which can be rotated to move the cursor around the screen
trackball in American English
(ˈtrækˌbɔl)
noun
a device built into or connected to a computer, containing a ball that can be freely rotated by hand in any direction so as to move or position the cursor
Examples of 'trackball' in a sentence
trackball
Inside each cubicle was a desk holding a twenty-one-inch monitor, a trackball, and a keyboard.