| A | B |
|---|
| triangle | A three-sided polygon |
| triceratops | A dinosaur with three horns-two long horns above the eyes and one short horn on the nose. |
| trigonometry | is a branch of mathematics that studies triangles and the relationships between their sides and the angles between these sides. |
| trilingual | able to speak three languages fluently |
| trimester | A period of three months; especially one of the three three-month periods into which human pregnancy is divided. |
| trio | A group of three people or things |
| trisect | To cut into three parts. |
| triatholn | A race with three parts: running, swimming, and bicycling. |
| tricycle | a three wheeled vehicle that is moved by pedals |
| trilateral | Having or involving three sides, countries, or parties. |
| trilogy | Three related plays or novels. |
| trinomial | A quantity expressed as a sum or difference of three terms |
| tripod | three-legged stool, table, or stand; used especially to support something like a camera. |
| Tritium | A radioactive isotope of hydrogen; atoms of this have three times the mass of ordinary hydrogen atoms. |
| triband | Supporting three frequency bands. (for example a phone that works on three different frequency bands so it has a greater coverage area) |
