If you discover something, you find it unexpectedly, like when you discover your favorite childhood stuffed animal in a box of old junk.
When you discover something, it can be by surprise or the result of a search. You might discover the fact that your dad used to travel with the circus as a trapeze artist or discover a band none of your friends ever heard of. Scientists often discover new substances, stars, or organisms. The Latin root discooperire, "uncover," combines the prefix dis-, or "opposite of," with cooperire, "to cover up."