What's the difference between a T-bone steak and a meteorite?

What's the difference between a T-bone steak and a meteorite?
One's meaty and the other's a little meteor.

Firstly, this joke is a pun. Meatier and Meteor are pronounced exactly the same in American English. The pun is that a meteorite is both of these things.

Secondly, this joke is a definitional joke. A meteorite is not actually a small meteor, but a meteor that struck the ground, so the jokester got that wrong (which might be funny to someone that knew this). Probably it wouldn't be funny to an English language pedant, but anyone else who knew what a meteorite is might find it funny.