Which term indicates that a medication should be given immediately?

The term indicating that a medication should be given immediately is "stat." This term originates from the Latin word "statim," meaning "immediately." In medical contexts, it signifies urgency, indicating that the medication is critical and needs to be administered without delay.

The other terms listed have specific meanings that differ from "stat." For instance, "prn" means "as needed," suggesting that medication should be administered only when necessary rather than on a strict schedule. "hs" stands for "hora somni," which means "at bedtime," indicating a scheduled time rather than an immediate need. Lastly, "ad lib" translates to "as desired," allowing for administration based on a resident's request or preference, rather than conveying urgency. Thus, "stat" is the accurate term for medications that require immediate attention.