In casino jargon, the term hit comes with several meanings.
If you are playing blackjack, hitting means requesting an additional card. If you hear someone say Hit me, you should most certainly not assume they are asking to be hit but are rather asking the croupier for another card. Speaking of blackjack, even the card received after hitting is called a hit.
Another thing you should know is that, if you are playing blackjack, you can ask for another card by tapping the table next to your cards or gently scratching your cards across the felt.
However, if you are playing video slots or slot machines, or some other casino games, hitting can be used to refer to landing a winning combination. For example, if you are playing poker, someone might say they hit a straight on the river while someone else might say they hit the jackpot from playing video slots.