Metaphor originated from the Greek word, metaphor which simply means to transfer. Analogy on the other hand came from the Greek word, analogia which means proportion. Given these etymologies, metaphor is a figure of speech that actually transfers the meaning of one thing directly on another unit.
Medicines that are taken âas neededâ are known as âPRNâ medicines. âPRNâ is a Latin term that stands for âpro re nata,â which means âas the thing is needed.â. Itâs important to know the difference between daily and âas neededâ medicines.hese instructions should include the following information: 1  How much medicine you can take in a set period of time. 2  When to take your PRN medication. 3  When to take scheduled and PRN medications for a single health problem.
BRAND NAME: Pravachol, Pravigard PAC (discontinued) DRUG CLASS AND MECHANISM: Pravastatin is an oral drug for lowering the cholesterol in the blood that contributes to the formation of plaques in the walls of arteries that obstruct the flow of blood, known as arteriosclerotic vascular disease. Obstruction of the flow of blood to the heart causes heart attacks.