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.
In chemistry, a hydron is the general name for a cationic form of atomic hydrogen, represented with the symbol H+ . The term proton refers to the cation of protium, the most common isotope of hydrogen.nlike other ions, the hydron consists only of a bare atomic nucleus. The hydron (a completely free or naked hydrogen atomic nucleus) is too reactive to occur in many liquids, even though it is sometimes visualized to do so by students of chemistry.