pre

The prefix "pre" adds the idea of "before" to the words it joins. It comes from the Latin prae, meaning "before," and it is used in many English words to show that something happens earlier, is done in advance, or belongs to an earlier time.

You see "pre" in everyday life all the time. We preheat ovens before baking, prepay bills before they are due, and preview movies before they are released. It can also describe something from an earlier period, such as prehistoric animals that lived before recorded history or prewar buildings that existed before a war.

It is also common in words about preparation. A preschool is for children before regular school. A prenatal visit happens before birth. In many cases, this prefix helps you quickly understand that one thing comes first and another thing follows later.

In school, science, and other formal writing, it keeps the same basic meaning. Precalculus is the math that comes before calculus, and preexisting means already there before something new happens. Sometimes it is written directly with the word, and sometimes it uses a hyphen, especially when that makes the word easier to read.

So, when you see a word starting with "pre," think of the idea of "before." It usually tells you that something happens early, is done in advance, or belongs to an earlier stage or time.