Focus

A point in which the rays of light meet, after being reflected or refrcted, and at which the image is formed; as, the focus of a lens or mirror.

A point so related to a conic section and certain straight line called the directrix that the ratio of the distace between any point of the curve and the focus to the distance of the same point from the directrix is constant.

A central point; a point of concentration.

To bring to a focus; to focalize; as, to focus a camera.

cause to converge on or toward a central point; "Focus the light on this image"

the concentration of attention or energy on something; "the focus of activity shifted to molecular biology"; "he had no direction in his life"

maximum clarity or distinctness of an image rendered by an optical system; "in focus"; "out of focus"

maximum clarity or distinctness of an idea; "the controversy brought clearly into focus an important difference of opinion"

direct one's attention on something; "Please focus on your studies and not on your hobbies"