triangle- a three-sided figure

 

triathlon- a race that combines three activities-swimming, bicycling, and running

 

triceratops- a dinosaur with three horns

 

tricycle- a vehicle with three wheels

 

trilateral- having or involving three sides, countries, or parties

 

trilingual- able to speak three different languages

 

trilogy- three related plays or novels

 

trio- a group of three people or things

 

tripod- a three-legged stool, table, or stand used to hold things, such as a camera

 

trisect- to cut into three parts