The adjective ocular means โpertaining to an eyeโ
something possessing eyes is oculate, and a person who
studies and understands eyes is an oculist
practising oculism (but an ocularist is a person who makes glass eyes).
Doctors have a whole collection of eye-related words
that need not detain us for long. Examples include
supraocular (โabove the eyeโ), periocular (โaround the eyeโ)
and the grim exoculation (โremoval of an eyeโ), but there are many more.
Monocular once meant โhaving one eyeโ, but that task has largely been taken over
by monoculous, leaving monocular to deal with โpertaining to one eyeโ. A monocule
is a creature with only one eye; a monoculist, monoculus
or monoculite is a one-eyed person. And of course a monocle is a single eye-glass.
Binocular has similarly surrendered the meaning โhaving two eyesโ to binoculate
reserving โpertaining to two eyesโ for itโs own use. A binocle is an opera glassโa
little pair of binoculars on a stick that can be used to observe the action on-stage.
For those with greater numbers of eyes than two, we have
trinocular (three), senocular (six), octonocular (eight),
centoculated (one hundred, reserved for the mythical all-seeing giant Argus Panoptes)
and the noncommittal multiocular (many).