What Are Prefix Words?

Whether you are just learning English or you already speak the language and simply want a review, knowing about prefix words is an excellent way to expand your vocabulary. A prefix is a letter or word that is added to the beginning of a word to alter its meaning. Frequently, prefixes change words into their opposites or add a degree of meaning to the word. A prefix word, therefore, is a word that has been modified by a prefix.

In order to understand how prefixes work, first it is important to know what a root, or real word is. Root words are words that can change into a new word by adding a beginning or ending to them. For example, "clear" is a root word. Simply by adding letters on either side of the root word "clear," several new words can be produced, such as "clearly," "cleared" or the prefix word "unclear."

A prefix always goes at the beginning of the word, as opposed to a suffix, which is a letter or group of letters added to the end of a word. A prefix can modify, change or expand the meaning of a word. For example, adding the prefix "mis-", which means "wrong," to the root word "spell" leaves you with the new word, "misspell," meaning spelling that is incorrect.

A word family is composed of a group of words that are centered around a common root word. According to the BBCi Skillwise website, "All of these words have grown from their root word. They share parts of the same spelling, and they are linked in terms of meaning." Learning suffix words, adverbs and tenses of words can help you further understand what prefix words are and expand your vocabulary even further. An example of a word family could come from the word "use." Other words stem from this root word, such as, "useless," "usable" and "used." The prefix "mis-" can be added to "use" as well, and would therefore be added to this word family as the prefix word "misuse."

There are countless examples of prefix words in the English language. The How to Study.com website gives a list of some of the most common prefix words along with the meaning of their prefixes:

"re-," meaning = again; examples: replay, resend, replace "hyper-," meaning = over; examples: hyperactive, hypersensitive, hyperventilate "un-," meaning = not; examples: unclear, unsure, undecided "pre-," meaning = before; examples: prepay, prepackage, predate "mis-," meaning = wrong; examples: misconduct, misspell, misunderstand