ocular

a. [ L. ocularis, ocularius, fr. oculus the eye: cf. F. oculaire. See Eye, and cf. Antler, Inveigle. ] 1. Depending on, or perceived by, the eye; received by actual sight; personally seeing or having seen; as, ocular proof. Shak. [ 1913 Webster ]

Thomas was an ocular witness of Christ's death. South. [ 1913 Webster ]

2. (Anat.) Of or pertaining to the eye; optic. [ 1913 Webster ]

n. (Opt.) The eyepiece of an optical instrument, as of a telescope or microscope. [ 1913 Webster ]