BIFOCALS

bifocals

(noun) (plural) eyeglasses having two focal lengths, one for near vision and the other for far vision

Source: WordNet® 3.1

Etymology

From bi- + focal (see focus), coined in 1824 by John Isaac Hawkins, inventor of trifocals. When the concept of bifocals was originally conceived by Benjamin Franklin, he called them double spectacles.

Noun

bifocals pl (plural only)

spectacles that have corrective lenses of two different powers; used by people who need both distance and reading glasses

Source: Wiktionary