1. A Double Feature: This is a common term in movie theaters, meaning two films are shown back-to-back in one evening. So, "nightly double" could refer to a double feature happening every night.
2. Double the Fun: It could be a slang term for something exciting or enjoyable that happens twice in one night. For example, "We had a nightly double - a delicious dinner followed by a concert!"
3. A Specific Event: If you heard the term in a particular context, like a restaurant or event, it could be a specific nightly event they offer.
To understand the meaning, more information is needed. Could you please provide some context? For example:
* Where did you hear this term?
* What was the conversation about?
* Were there any other clues?
With more information, I can help you decipher the meaning of "nightly double"!