The most common and most likely answer to this crossword clue is the 9 letter word CHIN-CHIN
I've seen this crossword clue in Financial Times
C
H
I
N
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C
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N
Buddy explains!
The straight part
We know that "Cheers/Hitchcock’s double feature" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cheers/hitchcock’s double feature = chin-chin.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CHIN-CHIN mean?
CHIN-CHIN verb- To greet; to toast.
- To say 'chin-chin'.
- A salutation, especially a drinking toast.
- Discussion, conversation, talk.