The most common and most likely answer to this crossword clue is the 3 plus 4 plus 1 plus 5 letter word OUT LIKE A LIGHT
I've seen this crossword clue in Financial Times
O
U
T
L
I
K
E
A
L
I
G
H
T
More clues leading to the result OUT LIKE A LIGHT
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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.