Which abbreviation signifies "before meals"?

The abbreviation that signifies "before meals" is "ac," which stands for "ante cibum" in Latin. This term is commonly used in medical and pharmacological settings to indicate that a medication should be taken prior to eating. This is important for certain medications where the absorption and effectiveness can be influenced by food intake, ensuring optimal therapeutic outcomes.

In contrast, the other options represent different timing with respect to meals or medication administration. For example, "pc" stands for "post cibum," indicating after meals, while "tid" means "three times a day," referring to the frequency of medication administration rather than its timing related to meals. Lastly, "hs" stands for "hora somni," which means "at bedtime," again unrelated to meal times. Understanding these abbreviations is crucial for proper medication management and patient instruction.