What does stolen base mean in baseball?

Answer 1

It means to run an extra base while the person who just hit the ball with the bat is running to a base.

Answer 2

If the catcher misses a ball pitch and it goes behind him and while he's getting it you run to the next base that is a stolen base.

Answer 3

if your on a base and the ball leaves the pitchers hands you can run to the next base. that's called stealing the base