The most common and most likely answer to this crossword clue is the 12 letter word UNDERPLAYING
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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 UNDERPLAYING mean?
UNDERPLAYING verb- To play in a subordinate, or in an inferior manner; to underact a part.
- To make something seem less important than it really is.
- To play a low card when holding a high one, in the hope of a future advantage.