SPELLING tri- = three

triangle  Noun  A three-sided figure  The triangle, a three-sided figure, can also be equilateral.

triathlon  Noun  A race that combines three activities – swimming, bicycling, and running  The man was preparing for the triathlon by running, swimming, and bicycling everyday.

triceratops  Noun  A dinosaur with three horns – two long horns above the eyes and one short horn on the nose  The triceratops is a three-horned reptile that is now extinct.

tricycle  noun  A vehicle with three wheels  Young children usually have to ride a three-wheeled vehicle called a tricycle.

trilateral  adjective  Having or involving three sides, countries, or parties  Something that has three sides is called trilateral.

trilingual  Adjective  Able to speak three different languages  The person was trilingual and could speak German, French, and Spanish.

trilogy  noun  Three related plays or novels  The trilogy of the three books were the best I have ever read.

trio  noun  A group of three people or things  If you and two friends got together to sing, it would be called a trio.

tripod  Noun  A three-legged stool, table, or stand used to hold things, such as a camera  We put the camera on the tripod, the three-legged stand.

trisect  verb  To cut into three parts  Amanda will cut the rectangular pizza into three equal pieces. She will trisect the pizza.