The most common and most likely answer to this crossword clue is the 10 letter word IDENTIFIED
I've seen this crossword clue in The Guardian
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D
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D
More clues leading to the result IDENTIFIED
- Given name Setter would change for definite
- Recognised a criminal perhaps but denied it, if found out
- Singled out when I refused to accept returned suit
- Criminal denied it if discovered
- Dine out, breaking diet if discovered
- Named condition one caught in current depressed state
- One study correct if diet’s connected
- Spotted fish fin with tide turning
- Named one treated like a god bored by religious work
Buddy explains!

The straight part
We know that "Singled out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case singled out = identified.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 IDENTIFIED mean?
IDENTIFIED verb- To establish the identity of someone or something.
- To disclose the identity of someone.
- To establish the taxonomic classification of an organism.
- To equate or make the same; to unite or combine into one.
- To have a strong affinity with; to feel oneself to be modelled on or connected to.
- To associate oneself with some group.
- To claim an identity; to describe oneself as a member of a group; to assert the use of a particular term to describe oneself.