What does the abbreviation "as" indicate in a medical context?

In a medical context, the abbreviation "as" stands for "auris sinistra," which is Latin for "left ear." This term is commonly used in prescriptions and medical documentation to specify that a treatment or medication pertains to the left ear.

Understanding this abbreviation is essential for accurate medication administration and patient safety, as it helps prevent errors that could arise from confusion between the left and right sides of the body. In contrast, the other options refer to different anatomical locations or routes of administration that do not coincide with the meaning of "as."