The term "focus grid" refers to a tool used in photography and videography to ensure that the camera is properly focused on the subject. Some synonyms for this term include "focusing screen," "viewfinder," and "focusing aid." Another term that is commonly used in photography is "depth of field preview," which allows the photographer to see how much of the image is in focus before taking a shot. Among videographers, the term "focus assist" may be used to refer to features such as peaking or zebras, which can be used to help ensure proper focus. Overall, these various terms all refer to techniques and tools used to achieve sharp and properly focused images.