[bi.fo.cal] adj [ISV] (1888) 1: having two focal lengths
2: having one part that corrects for near vision and one for distant vision "a ~ eyeglass lens"
[2]bifocal n (1899) 1 pl: eyeglasses with bifocal lenses
2: a bifocal glass or lens
[bi.fo.cal] adj [ISV] (1888) 1: having two focal lengths
2: having one part that corrects for near vision and one for distant vision "a ~ eyeglass lens"
[2]bifocal n (1899) 1 pl: eyeglasses with bifocal lenses
2: a bifocal glass or lens
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012