You searched for: “trifocal lens”
trifocal lens (s) (noun), trifocal lenses (pl)
A lens with three parts of different refracting powers: the upper for distant sights, the middle for intermediate views, and the lower for near visions.
This entry is located in the following units: focus-, foci- (page 2) lenti-, lent-, lens- + (page 2)