OD/OS

Walter Bailey, preservation of eyesight, published 1587-88

OD means right eye. oculus dextrus.

OS means left eye. oculus sinister.

These are holdover terms from cool latin times! We still use them. Conventionally, OD always comes before OS. Optometrists use this convention as standard.

But why do you use them??? Just use left eye right eye??? Why do you have to make everything complicated????

If you have to write out 'left eye and right eye' every single time, that can become tedious especially when you're talking to cool vision improvement people who know what they're talking about.

'OD/OS' is five characters. 'left eye, right eye' is nineteen characters. Use the longer version if you insist :P

See also

Prescription