| Main Entry: | twin paradox |
| Part of Speech: | n |
| Definition: | a supposed paradox in relativity theory that if one of a pair of twins journeys near the speed of light and returns, that win will have aged less than the twin left behind |
| Usage: | science |
An effect predicted by the general theory of relativity: if one of a pair of twins remains on Earth, and the other travels in a rocket at a speed near the speed of light, the traveling twin will be younger than the earthbound twin upon returning to Earth. This effect has been verified experimentally by measurements with atomic clocks.