To disprove something means to prove that it's false or wrong by showing clear evidence against it. When scientists disprove a theory, they demonstrate through experiments or observations that the theory doesn't match reality. If someone claims that all birds can fly, you could disprove that statement by pointing to penguins and ostriches.

Disproving requires actual evidence that demonstrates falsehood. You need facts, observations, or logical demonstrations that show why something cannot be true. If your friend insists they can hold their breath for ten minutes, you could disprove their claim with a simple stopwatch test. When a detective disproves a suspect's alibi by finding video footage showing them somewhere else, that evidence makes the false statement obvious.

The word is especially important in science and investigation, where proving something false is just as valuable as proving something true. Scientists spend careers trying to disprove existing theories, because finding out what's wrong helps everyone get closer to what's actually right. Mathematics also uses disproof constantly: you can disprove that all prime numbers are odd by pointing to the number 2, which is prime and even.

Notice that disprove is different from simply not proving something. If you can't prove your theory, that doesn't mean someone has disproved it. To disprove something, you must show positive evidence that it's false.