Have you ever seen O.D. or O.S. on an eye prescription and wondered what they mean?
Today’s word — Oculus — explains it all.
👁 What Does “Oculus” Mean?
Oculus is a Latin word that means eye.
It appears frequently in terminology and patient records — especially in ophthalmology and optometry.
When you see abbreviations like O.D. or O.S. on a prescription or chart, they come from this word.
🔍 Clinical Usage
In Latin-based medical notation:
| Abbreviation | Latin Term | English Meaning |
|---|---|---|
| O.D. | Oculus Dexter | Right eye |
| O.S. | Oculus Sinister | Left eye |
| O.U. | Oculus Uterque | Both eyes |
You’ll often find Oculus and its abbreviations — O.D., O.S., and O.U. — in patient charts, prescriptions, and ophthalmology notes. They may also come up during eye examinations or training discussions with other healthcare professionals.
Example:
“Apply ointment to O.S. twice daily.” → Apply to the left eye twice a day.
🎥 Watch the Short Video
👉 Watch our 20-second clip: Oculus –Learn how to pronounce it.
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