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bifocal
bi·fo·cal B0236900 (bī-fō′kəl, bī′fō′-)adj.1. Having two focal lengths.2. Having one section that corrects for distant vision and another that corrects for near vision, as an eyeglass lens.3. Having two distinct goals or objects of attention: a bifocal approach to the problem.pl.n. bi·fo·cals (bī′fō′kəlz, bī-fō′-) Eyeglasses with bifocal lenses.
bi·fo′cal·ism n.bifocal (baɪˈfəʊkəl) adj1. (General Physics) optics having two different focuses2. (Medicine) relating to a compound lens permitting near and distant visionbi•fo•cal (baɪˈfoʊ kəl, ˈbaɪˌfoʊ-)
adj. 1. having two foci. 2. (of an eyeglass or contact lens) having two portions, one for near and one for far vision. n. 3. bifocals, bifocal eyeglasses. [1885–90, Amer.] Thesaurus| Adj. | 1. | bifocal - having two foci; "bifocal eyeglasses"optics - the branch of physics that studies the physical properties of lightcentral - in or near a center or constituting a center; the inner area; "a central position" |
Translationsbifocal (baiˈfəukəl) adjective (of lenses) having two points of focus, which help people to see things close at hand and things far away. (鏡片)雙焦點的 （指眼镜片）双焦点的 bifocal
bifocal1. Optics having two different focuses 2. relating to a compound lens permitting near and distant vision bifocal
bifocal [bi´fo-kal] of a lens, having two areas with different refractive powers.bifocal glasses eyeglasses in which each lens is made up of two segments of different refractive powers, or strength. Generally, the upper part of the lens is used for ordinary or distant vision, and the smaller, lower section for near vision, for close work such as reading or sewing. Bifocal eyeglasses may be prescribed for presbyopia, which often occurs with aging.bi·fo·cal (bī-fō'kăl), Having two foci.bifocal (bī-fō′kəl, bī′fō′-)adj.1. Having two focal lengths.2. Having one section that corrects for distant vision and another that corrects for near vision, as an eyeglass lens.3. Having two distinct goals or objects of attention: a bifocal approach to the problem.pl.n. bifocals (bī′fō′kəlz, bī-fō′-) Eyeglasses with bifocal lenses.
bi·fo′cal·ism n.bi·fo·cal (bī-fō'kăl) Having two foci. bifocal Having two different foci. In bifocal spectacles each lens has a lower segment of greater power for convenience in reading.bifocal
Related to bifocal: bifocal glassesWords related to bifocaladj having two fociRelated Words |