The most common and most likely answer to this crossword clue is the 3 plus 2 letter word ONE UP
I've seen this crossword clue in Independent
O
N
E
U
P
More clues leading to the result ONE UP
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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 ONE UP mean?
ONE UP noun- An item that grants the player an extra life in the game, staving off game over by one more try.
- In a game with multiple players, an indicator or identifier of player 1.
- (especially in phrases like get one up on someone) An advantage over someone.
- To outdo, to do something slightly better than a competitor's prior effort.