zoom
In photography, to alter the size of an image from a stationary camera position without changing perspective by using a zoom lens to increase or decrease the focal length. In cinematography, this type of lens appears to make the camera advance toward the subject when zooming in, or retreat from it when zooming out.
In word processing software, a feature that allows the user to enlarge or reduce the size of a page displayed on the screen, usually by a fixed percentage or in small increments. In Web browsers, a feature that allows the viewer to enlarge all or a portion of an image, sometimes in increments. Also, a feature on some photocopy machines that allows the user to specifiy the extent to which an original will be enlarged or reduced in size in copying.