The most common and most likely answer to this crossword clue is the 3 plus 4 plus 6 letter word OFF ONES ROCKER
I've seen this crossword clue in Financial Times
O
F
F
O
N
E
S
R
O
C
K
E
R
More clues leading to the result OFF ONES ROCKER
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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.