Definition: A hit is a general term used to describe the number of autographed cards, memorabilia cards and - depending on the product - rookie cards in a box of sports cards. It can also be used as a verb.
Examples:
Noun: From what I understand, you can expect four hits in every box of those baseball cards.
Verb: I really wanted a card of the top quarterback, but I opened packs all day and didn't hit any of his rookies.