What does the abbreviation O.S. refer to?

The abbreviation O.S. stands for "oculus sinister," which is Latin for "left eye." In medical terminology, abbreviations are often derived from Latin terms, and O.S. is specifically used to reference the left eye in prescriptions and other healthcare documentation. Understanding these abbreviations is crucial for medication aides, as they ensure proper administration of medications and assist in avoiding any mistakes related to which eye medication is prescribed or administered. This knowledge is essential for providing safe and effective care to patients.