Word Study
bifocal
CIDE DICTIONARY
bifocal, a. [Pref. bi-+ focal.].
Having two foci, as some spectacle lenses. [Webster 1913 Suppl.]
bifocal, n. [Pref. bi-+ focal.].
a bifocal lens. [PJC]
OXFORD DICTIONARY
bifocal, adj. & n.
--adj. having two focuses, esp. of a lens with a part for distant vision and a part for near vision.
--n. (in pl.) bifocal spectacles.
--adj. having two focuses, esp. of a lens with a part for distant vision and a part for near vision.
--n. (in pl.) bifocal spectacles.
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