Etymology is the study of the origins and meanings of words. Many words in the English language have been formed by combining root words, which can be traced back to the early languages where those words and concepts first appeared. These early languages are usually Latin and Greek, though some common words have come into the English language from the early Germanic languages, or from the Middle East. If you know how to look at a word and identify the roots contained in it, you’ll have a good idea of what that word means, and what other words might be related in meaning.

An example of a Greek root found in several English words is epi, meaning “near, close to” or “upon.” This Greek root is often found at the beginning of words, as a prefix. Once you see the sequence epi- at the start of a word, you can look at the rest of the word to find out exactly what is “near or close by.” Here are some useful English vocabulary words with this prefix:

episode (EH-pih-sohd) noun
An episode is a discrete event or happening, but one that is connected to other events in a series which occur or recur regularly. The adverbial form of this noun is episodic.
Example 1: Alan takes medication to help control his episodes of tinnitus.
Example 2: The next episode of “Who Wants to be a Millionaire?” is expected to draw nine million viewers.

epitaph (EH-pih-taff) noun
Adding the Greek word taphos (“tomb”) to our prefix, we get the English word for an inscription on a grave marker or tombstone. In the past, an epitaph was also the name for a poem eulogizing the deceased, often hung on the entrance to the crypt where they were buried.
Example: I cannot bid you bid my daughter live; that were impossible; but, I pray you both, possess the people in Messina here how innocent she died; and if your love can labour aught in sad invention, hang her an epitaph upon her tomb, and sing it to her bones: sing it to-night. – from “Much Ado About Nothing” by William Shakespeare

epicenter (EH-pih-sehn-tur) noun
Unfortunately, this word has been in the news quite often lately; the focal point of an earthquake is referred to as the epicenter. In a more metaphorical sense, the word is often used to mean something or someone that is in the center of (often the cause of) an eventful, chaotic, or complicated situation.
Example: In the 1990s, bands like Nirvana and Pearl Jam made Seattle the epicenter of the grunge movement.

We’ll just add this as a brief epilogue: to quickly increase your ability to learn and memorize new English vocabulary words, make etymology the centerpiece of your study program!