(Busted) means the myth was disproved.To disprove means "to show that (something) is false or wrong." Also another common English word used in place of busted is debunked. Example : Scientists just (debunked) the biggest myth about coffee Just to add a point, it could also mean that you (discover the truth). It really depends on what context it's used in. The popular American Television show MythBusters will say a myth has been busted when it has been disproved, and confirmed when a myth was discovered to be true.

It means that they disproved the biggest myth about coffee.

Busted in this situation means that you (discover the truth)

discovered!!!! yes!

Busted means found out or discovered.