Number Prefixes

Number prefixes are prefixes that are derived from numbers or numerals. They are used to create some words you will encounter. Recognizing these prefixes and the numbers they represent will help you to learn and better understand the meanings of such words

Here are prefixes that represent the numbers 1 though 10. Next to each prefix are examples of words that are formed using the number prefix, along with the meanings of the words.

1	mono	monologue	A long speech or performance given by one person.
		monorail	A railroad track that has only one rail.
1	uni	unicorn	An imaginary animal that has one horn.
		unicycle	A pedaled vehicle that has one wheel.
2	bi	bicycle	A pedaled vehicle that has two wheels.
		biennial	An event that occurs every two years.
2	du	duet	A piece of music written for two singers or musical instruments.
		duplex	A house divided into two units with separate entrances.
3	tri	triangle	A plane figure that has three angles and three sides.
		tricycle	A pedaled vehicle that has three wheels.
4	quad	quadrangle	A plane figure that has four angles and four sides.
		quadruple	A number or amount four times as great as another.
5	penta	pentagon	A plane figure that has five angles and five sides.
		pentathlon	An athletic contest that consists of five events.
5	quint	quintet	A group of five persons or things.
		quintuplets	Five children born at the same time to the same mother.
6	hexa	hexagon	A plane figure that has six angles and six sides.
		hexagram	A six-pointed star.
7	sept	septenary	A period of seven years.
		septennial	An event that occurs every seven years.
8	oct	octet	The first eight lines in a sonnet.
		octopus	A saltwater animal with eight arms.
9	nov	November	The ninth month of the year in the ancient Roman calendar.
		novena	Nine days of prayers or services.
10	deca	decade	A period of ten years.
		decathlon	An athletic contest that consists of ten events.

You can expand your vocabulary by recognizing these number prefixes when they appear at the beginnings of words.