Prefixes

Reference list: A reference list with all common prefixes, roots, and suffixes is available for review at the end of this chapter to help you study.

Prefixes

Not every word has a prefix. When a prefix is present, it adds meaning at the very beginning of the word. That extra meaning gives you clues about how the word is used and what it means. Learning a few common prefixes can help you work out the meaning of many unfamiliar words.

For example, the prefix “a-” often makes a word negative because it means “not” or “without.” The word “typical” means “common,” but “atypical” means “not common.” A small change at the start of a word can shift the meaning a lot.

Next, you’ll look at several common prefixes and example words so you can see how prefixes shape meaning.

Common prefixes:

Anti-

Meaning: against

Example words: Antibiotic, Antisocial, Antipathy, Antagonist, Antonym

• Antibiotic: Anti-bio, meaning “against [something] biological or living.” An antibiotic is a medicine that kills living bacteria.

• Antisocial: Anti-social, meaning “against [being] social” or “against society.” People who are antisocial are hostile to others and typically shun society.

• Antipathy: Anti-path, meaning “against feeling” or “disliking.” Antipathy is a dislike of someone or something.

• Antagonist: Anti/anta-gonist, meaning “against a contender for a prize.” An antagonist is a rival to someone who wants something, often used to describe the person working against the main character (protagonist) in a piece of fiction.

Knowledge check: What does the word antonym mean?

(spoiler)

Anti/ant-nym, meaning “against [a] name.” An antonym is a word that has an opposite meaning (or “name”) as another word. For instance, “fast” and “slow” are antonyms of one another.

Co-

Meaning: together

Example words: Cooperate, Cohabitate, Congregate, Coherent, Correct

• Cooperate: Co-operate, meaning “operating or working together.” When people cooperate, they work together to achieve a goal.

• Cohabitate: Co-habitate, meaning “living together.” Cohabitating is living in the same place as someone or something else.

• Congregate: Co-greg, meaning “flocking together.” To congregate is to gather (or “flock”) together.

• Coherent: Co-her, meaning “stick together.” When something is coherent, it’s understandable, makes sense, or “sticks together.”

Knowledge check: What does the word correct mean?

(spoiler)

Co-rect, meaning “straight together.” If something is correct, it is aligned, is true, or comes together straightly or rightly.

Inter-

Meaning: between

Example words: Interact, Interjection, Interface, Intergenerational, Intersect

• Interact: Inter-act, meaning “do/act between.” To interact with something or someone is to act between or on one another mutually.

• Interjection: Inter-ject, meaning “throw between.” To interject is to interrupt or come between something.

• Interface: Inter-fac, meaning “make between.” An interface is a system that connects systems.

• Intergenerational: Inter-gen, meaning “between birth.” When something is intergenerational, it occurs between multiple generations.

Knowledge check: What does the word intersect mean?

(spoiler)

Inter-sec, meaning “cut between.” To intersect something is to cut across, overlap, or go through it.

Re-

Meaning: again or back

Example words: Reanimate, Recognize, Reinforce, Rehydrate, Repellant

• Reanimate: Re-anim, meaning “alive again.” To reanimate is to bring something back to life.

• Recognize: Re-cogn, meaning “know again.” When we recognize something, we remember it from before and know it again.

• Reinforce: Re-fort, meaning “strong again.” To reinforce something is to build it up and make it stronger.

• Rehydrate: Re-hydr, meaning “again water.” Rehydrating something is to add water to it.

Knowledge check: What does the word repellant mean?

(spoiler)

Re-pel, meaning “drive back.” Something that is repellent is something disgusting that a person would want to drive back or away.

Sub-

Meaning: under or below

Example words: Subtract, Submerge, Subterranean, Suburb, Support

• Subtract: Sub-tract, meaning “pull below.” When we subtract something, we remove it (or pull it away from) something else.

• Submerge: Sub-merg, meaning “dip below.” To submerge something is to dip it into a liquid.

• Subterranean: Sub-terr, meaning “below the land.” When something is subterranean, it is below ground.

• Suburban: Sub-urb, meaning “below or outside a city.” A suburb is a neighborhood near a city.

Knowledge check: What does the word support mean?

(spoiler)

Sub-port, meaning “carry [from] below.” To support something is to hold something up from the bottom.