monocle

An eyeglass for one eye.

In photography, an uncorrected spectacle-lens, usually periscopic, of about 1½ inches diameter, and of a focus of 2 inches and upward.

A monoculous or one-eyed animal; a monocule.

A glass for one eye; a single eye-glass.

An eyeglass for one eye.

a single lens, usually in a wire frame, and used to correct vision for only one eye

lens for correcting defective vision in one eye; held in place by facial muscles