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Prefixes and combining forms—T to Z

Want to expand your vocabulary? Figure out the meaning of an unknown word? If so, learning to identify prefixes and understanding their meaning will help you do just that.

What's a prefix? It's a word form that attaches itself to the beginning of another word (the base word) to change the word's meaning. For example, the prefix ex means “former.” Connect it to the base word friend, and you're no longer on friendly terms—you're an ex-friend. Big difference!

But what about ex in the word exclude? Is that a prefix, too? No, it isn't. It's a combining form meaning “out,” and it attaches itself to a root word, not a base word. Remove the ex, and you're left with the root clude, which makes no sense by itself.

Have fun increasing your word knowledge with these common English prefixes and combining forms.

T

tele

Meaning 1: from a distance

Example: Once a week, I telework from home.

Meaning 2: television

Example: The program will be telecast at 9:00 p.m.

Meaning 3: via telecommunications

Example: Telehealth provides health care services through technology.

tetra

Meaning: four

Example: A tetragon is a four-sided shape.

theo

Meaning: God

Example: Theology is the study of religions.

therm

Meaning: heat

Example: A thermometer measures body heat.

topo

Meaning: place

Example: Canada's topography is dominated by the Canadian Shield.

toxi, toxico

Meaning: poison

Examples: Some toxins are released through the skin.
Toxicology is the study of poisons.

trans

Meaning 1: across

Example: We're taking a transatlantic cruise!

Meaning 2: beyond

Example: His behaviour transcends logic.

Meaning 3: through

Example: Cook the onions until they are translucent.

tri

Meaning: three

Example: The child was riding her tricycle.

U

ultra

Meaning: immensely, overly

Example: Shoppers will enjoy the car's ultramodern design.

un

Meaning 1: not

Example: I am unaccustomed to hot, humid summers.

Meaning 2: absence of

Example: A wave of unrest grips the city as protesters take to the streets.

Meaning 3: reversal of

Example: Can you unlock the door for me?

uni

Meaning: one

Example: On Sesame Street, Ernie's friend Bert sports a unibrow.

V

vice

Meaning: a person who replaces someone else in a certain function

Example: The vice-principal is in charge during the principal's absence.

viti

Meaning: vine

Example: The growth of Prince Edward County's wine and viticulture industry is phenomenal.

Z

zoo

Meaning: animal

Example: A zoologist studies animals.