Bifocal
chiefly optics. having two foci.
(of an eyegl-ss or contact lens) having two portions, one for near and one for far vision.
bifocals, bifocal eyegl-sses or contact lenses.
historical examples
encyclopaedia britannica, 11th edition, volume 11, slice 1 “franciscans” to “french language” various
parallel paths thomas william rolleston
adjective
(optics) having two different focuses
relating to a compound lens permitting near and distant vision
adj.
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capable of being folded into two parts, as with leaves that are hinged together: a bifold door; bifold shutters. historical examples hints on cheese-making thomas day curtis
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having two leaves. adjective having only two leaves adj.
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having two leaflets. adjective (of compound leaves) consisting of two leaflets
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having or combining two forms, as a centaur or mermaid. historical examples the genus pinus george russell shaw adjective having or combining the characteristics of two forms, as a centaur
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of, relating to, or involving two genera. adjective (of a hybrid plant) derived from parents of two different genera