The most common and most likely answer to this crossword clue is the 8 letter word LOOSENER
I've seen this crossword clue in Independent
L
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More clues leading to the result LOOSENER
Buddy explains!
The straight part
We know that "warm-up act" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case warm-up act = loosener.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 LOOSENER mean?
LOOSENER noun- Something that loosens
- A usually inaccurate delivery bowled early in a bowler's first over.
- An alcoholic drink that makes a person relax.