Disputable means open to debate or disagreement because reasonable people might see it differently. If something is disputable, you can argue about it without being obviously wrong.

Whether chocolate ice cream tastes better than vanilla is disputable: people have different preferences, and neither answer is right or wrong. But whether water freezes at 32°F isn't disputable: that's a fact you can prove. In a classroom discussion, the most interesting questions are often disputable ones, where students can present different viewpoints and evidence.

The word comes from dispute, which means to argue or disagree about something. Scientists might dispute each other's theories, presenting evidence for different conclusions. Friends might dispute who won a close race. A disputable claim is one where thoughtful people, looking at the same information, might reasonably come to different conclusions.

The opposite is indisputable: something so clearly true that no reasonable person would argue against it. If your teacher says “It's indisputable that you turned in your homework late,” there's no room for debate: you both know what time it was turned in. But if she says your essay's main argument is disputable, she means other readers might interpret the evidence differently, which isn't necessarily bad. Many of the most important questions in history, science, and literature remain disputable, which is exactly what makes them worth discussing.