Wiktionary
alt. 1 A place on a form that can be checked or not. 2 (context graphical user interface English) A feature on a UI element such as a webpage that can be marked or not to indicate whether it is selected. n. 1 A place on a form that can be checked or not. 2 (context graphical user interface English) A feature on a UI element such as a webpage that can be marked or not to indicate whether it is selected.
Wikipedia
A checkbox (check box, tickbox, tick box) is a GUI widget that permits the user to make a binary choice, i.e. a choice between one of two possible mutually exclusive options. For example, the user may have to answer 'yes' (checked) or 'no' (not checked) on a simple yes/no question.
Checkboxes are often shown on the screen as a square box that can contain white space (for false) or a tick mark or × (for true), as shown ( ☐ or ☑, respectively). A caption describing the meaning of the checkbox is normally shown adjacent to the checkbox. Inverting the state of a checkbox is done by clicking the mouse on the box, or the caption, or by using a keyboard shortcut, such as the space bar.
Often, a series of checkboxes are presented, each with a binary choice between two options. Then the user may select several of the choices. Compare this to a radio button, in which only a single option is selectable from several mutually-exclusive choices.
Usage examples of "checkbox".
GUIs have virtual pushbuttons too, of course, but they also have other types of virtual controls, like radio buttons, checkboxes, text entry boxes, dials, and scrollbars.