v.1. To herd some cattle together from various places: In the evening it's time to round up the herd. The ranchers rounded the younger cattle up to brand them.
2. To seek out and bring some people or things together; gather some people or things: We rounded up all of our neighbors to help clean the park. Go out and round the kids up for dinner.
3. To change some exact number to the nearest whole number above it: The statistician rounded 4.612 up to 5. When you take the test, round up your answers.