a. and sb. [f. L. bīnī two each + oculī eyes + -AR; cf. F. binoculaire.]
† 1. Having two eyes; binoculate. ? Obs.
1713. Derham, Phys. Theol., VIII. iii. (1754), 361. Most animals are binocular, Spiders for the most Part octonocular.
2. Performed by or adapted to both eyes.
1738. R. Smith, Opticks, 387. This observation gave rise to the contrivance of a binocular telescope.
1876. Foster, Phys., III. ii. (1879), 509. Binocular vision affords us a means of judging of the solidity of objects.
1879. Rutley, Stud. Rocks, vii. 47. Many observers prefer to work with binocular microscopes.
1879. Rood, Chromatics, 160. Binocular mixture of colours produces more or less lustre.
B. sb. (Short for binocular glass.) A field-glass or opera-glass in the use of which both eyes are employed in viewing an object; a BINOCLE. Also applied to a binocular microscope.
1871. M. Collins, Mrq. & Merch., III. iv. 114. I shall keep this binocular.
1877. W. Thomson, Voy. Challenger, I. i. 15. One of Smith and Becks binoculars is more convenient for observing large foraminifera, by reflected light.