What does a drink "on the rocks" mean?

I'm thinking it's straight booze over ice? I googled it but it wasn't clear if it was mixed with soda. Also, does a bar charge for each shot that goes in?

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1 y
Thanks for all your opinions! I actually went out for dinner tonight, which was nice and I bothered the bartender a bit! It is generally true, that "on the rocks" means straight booze over ice, but they do ask customer's, such as myself, if they want their soda on the rocks or just the can. Technically, a lot of you were right when you said it's any iced drink. He also went on about "Neat" drinks", which some of you mentioned. That's a drink that's poured directly into the glass, no soda or ice.
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1 y
But they said they go by how the customer calls the drink. He said he has a customer that goes into his bar and says, "Give me a Jack in the tall shot glass", which means, give me a Jack in a normal glass without ice or soda. 😂

What does a drink "on the rocks" mean?
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