Roughly means approximately or not exactly. When you measure something roughly, you're getting close to the right answer without worrying about being perfectly precise. If someone asks how long it takes to walk to school and you say “roughly fifteen minutes,” you mean it might be thirteen minutes one day or seventeen the next, but fifteen is close enough.

The word appears constantly in everyday life. A recipe might call for roughly two cups of flour when the exact amount isn't critical. A teacher might say there are roughly 180 days in a school year, meaning somewhere close to that number. Scientists use it when discussing estimates: the Grand Canyon is roughly one mile deep, and dinosaurs went extinct roughly 66 million years ago.

Roughly can also describe how something is done: in a harsh, ungentle way. If you handle a book roughly, you're being careless with it, maybe bending pages or dropping it. A hockey player who plays roughly uses aggressive physical contact.

When you see roughly in your reading, it's usually telling you that precision isn't the point. The writer wants you to understand the general size, time, or amount without getting hung up on exact details.