A prefix is a word part that attaches to the front of a root or to an existing word to create a new word. The prefix “micro,” for example, attached before the root “scope” gives us the word “microscope.” An “existing word,” it may be noted, may already contain a prefix. For example, we can add the prefix “in-” to the word “complete,” which itself is made up of the prefix “com-” attached to the root “plete.” The word “incomplete” then consists of two prefixes attached to a root. Similarly, the word “mistranslate” contains the two prefixes “mis-” and “trans-” standing before the root “lat.”
The list below contains some of the most common and important prefixes in English. All the prefixes in this list derive from Latin or Greek, except the two “un-” prefixes, which derive from Old English.
Additional example words for each prefix in the list below can be found by going to A-Z Word Parts under Search Tools in our dictionary, filtering the list there for “Prefixes” and browsing through the list. One may also use the search box on the A-Z Word Parts page to search the list for a particular prefix. Click here to learn more about how to use the Wordsmyth Word Parts database.
| prefix | meaning | example word |
|---|---|---|
| anti- | against | antibacterial, antiwar, antislavery, anticancer drug |
| auto- | self | automobile, autobiography, autograph, automatic |
| bi- | two | bicycle, bilingual, bisect, binoculars |
| circu-, circum- | around | circular, circus, circulate, circumnavigate |
| com- | with; together | combine, combat, compose, component |
| dis- | not; apart; reverse, negate | disappear, disagree, dishonest, disbelief |
| en-1, em-1 | to put into; cause to be or have | enjoy, envelope, enlarge, employ |
| ex- | out, out of, away from | exit, exhaust, exclude, export |
| il-2 im-2 in-2 ir-2 | not, without | illegal, impossible incomplete, incorrect, irregular |
| inter- | between, among | international, internet, interrupt, intersect |
| micro- | small | microscope, microsurgery, microbe, microwave |
| mis- | bad, badly, wrongly | mistake, misunderstand, misbehave, mistreat |
| multi- | many | multiply, multicolored, multitude, multitask |
| non- | not | nonsense, nonfiction, nondairy, nonessential |
| pre- | before | predict, precede, preheat, prejudge |
| re- | again, back, back again | rewrite, review, redo, rebuild, recall |
| sub- | under, below | subway, submarine, subcategory, submerge |
| trans- | across, over, to the other side | transport, transit, transatlantic, translate |
| un-1 | not | unnecessary, unable, unusual, unequal |
| un-2 | reverse (an action) | untie, undo, unbutton, unlock |
See also:
Word Parts I: basic roots
Word Parts II: basic suffixes
Word Parts III: Intermediate level suffixes
Learn more about the Wordsmyth word parts database and how this unique feature can be used in facilitating vocabulary learning and teaching.