| A | B |
| quadrant | one out of four equal parts of a circle; one section of a four section coordinate grid |
| quadrilateral | a plane figure in geometry that has four sides (including a square, rectangle, rhombus, parellelogram, and trapezoid) |
| quadrisect | to dut or divide into four equal parts |
| quadruped | an animal with four feet |
| quadruple | to create four times as much or as many of something |
| quadruplet | a collection or group of four; one of four babies born from the same mother at the same time |
| triatholon | a race that combines three activities-swimming, bicycling and running |
| triceratops | a dinosaur with three horns--two long horns above the eyes and a short horn on the nose |
| trilateral | having or involving three sides, countries or parties |
| trilogy | three related plays or novels |
| trio | a group of three people or things |
| trisect | to cut into three parts |