bifocal

[ bahy-foh-kuh l, bahy-foh- ]
/ baɪˈfoʊ kəl, ˈbaɪˌfoʊ- /

adjective

Chiefly Optics. having two foci.
(of an eyeglass or contact lens) having two portions, one for near and one for far vision.

noun

bifocals, bifocal eyeglasses or contact lenses.

Origin of bifocal

An Americanism dating back to 1885–90; bi-1 + focal

Example sentences from the Web for bifocal

British Dictionary definitions for bifocal

bifocal
/ (baɪˈfəʊkəl) /

adjective

optics having two different focuses
relating to a compound lens permitting near and distant vision

Medical definitions for bifocal

bifocal
[ bī-fōkəl, bīfō′- ]

adj.

Having two focal lengths.
Having one section that corrects for distant vision and another that corrects for near vision.