The most common and most likely answer to this crossword clue is the 5 letter word RAVED
I've seen this crossword clue in Independent
R
A
V
E
D
More clues leading to the result RAVED
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The straight part
We know that "Was flipping" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case was flipping = raved.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 RAVED mean?
RAVED verb- To wander in mind or intellect; to be delirious; to talk or act irrationally; to be wild, furious, or raging.
- To speak or write wildly or incoherently.
- To talk with unreasonable enthusiasm or excessive passion or excitement; followed by about, of, or (formerly) on.
- To rush wildly or furiously.
- To attend a rave (dance party).