monocle
noun /ˈmɒnəkl/
/ˈmɑːnəkl/
- a single glass lens for one eye, held in place by the muscles around the eye and used by people in the past to help them see clearlyWord Originmid 19th cent.: from French (earlier in the sense ‘one-eyed’), from late Latin monoculus ‘one-eyed’.