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Prefixes and combining forms—Q to S

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.

Q

quadr, quadri, quadru

Meaning 1:four, fourth

Examples:This exercise strengthens your quadriceps, a group of four muscles.
He underwent quadruple bypass surgery.
Québec City celebrated its quadricentennial in 2008.

Meaning 2:square

Example:In a quadratic equation, the variable is squared.

quint

Meaning:five

Example:The Dionne quintuplets were born in Corbeil, Ontario.

R

re

Meaning:again

Examples:I'll have to redo the calculations.
Thank you for re-electing me to the House of Commons.
You'll have to re-form the clay.

retro

Meaning:back

Example:She is entitled to retroactive pay since she has been acting in her new position for three months.

rhino

Meaning:nose

Example:Rhinoplasty is plastic surgery on the nose.

rhodo

Meaning:rose-coloured

Example:Rhododendrons produce fragrant blossoms.

S

seismo

Meaning:earthquake

Example:A seismologist studies earthquakes.

semi

Meaning 1:half

Example:We arranged the chairs in a semicircle for the ceremony.

Meaning 2:in part, partially, somewhat

Example:Prince Edward County produces excellent semi-dry white wines.

Meaning 3:twice in a period of time

Example:The conference is held semi-annually.

sesqui

Meaning:one and a half

Example:Canada will celebrate its sesquicentennial in 2017.

socio

Meaning:society

Example:Sociology is the study of social behaviour among humans.

somni

Meaning:sleep

Example:The music had a somniferous effect on the child: she fell asleep.

sona, soni

Meaning:sound

Examples:Marine biologists used sonar technology to save the stranded whale.
An aircraft breaking the sound barrier makes a sonic boom.

sub

Meaning 1:below

Example:You can easily install tiles over this subfloor.

Meaning 2:lower in rank

Example:She chairs a subcommittee on human rights.

Meaning 3:next to, nearly

Example:Come visit Canada's subarctic regions.

sucr, sucro

Meaning:sugar

Example:Table sugar is also known as sucrose.

super

Meaning 1:over, more than

Examples:A supersonic jet travels at speeds greater than the speed of sound.
Superman is a fictional character with supernatural powers.

Meaning 2:to an intense or excessive degree

Example:Jessica fainted when she saw the supermagnified image of the spider.

Meaning 3:greater than others of the same type

Example:A superbug is resistant to almost all antibiotics.

sym, syn

Meaning 1:alike

Examples:The human body is not perfectly symmetrical.
A synonym for the word "beautiful" is "attractive."