To act dishonestly means to deliberately deceive others or hide the truth. When someone behaves dishonestly, they might lie about breaking a classroom rule, copy someone else's homework and claim it as their own, or pretend they returned a borrowed item when they actually lost it.

Dishonesty involves knowing what's true or right but choosing to misrepresent it anyway. It's different from making an innocent mistake or being confused about facts. If you accidentally give wrong directions because you genuinely thought you knew the way, that's not dishonest. But if you tell your friend the party starts at 3:00 when you know it starts at 2:00 because you want to arrive first, that's acting dishonestly.

The word often appears in warnings: “Anyone who completes the assignment dishonestly will receive no credit.” People might act dishonestly in small ways, like exaggerating a story to seem more impressive, or in serious ways, like a politician taking bribes or a business owner cheating customers.

Once someone develops a pattern of dishonest behavior, they earn a reputation for dishonesty that's hard to shake. Others may stop believing them even when they're telling the truth.