The most common and most likely answer to this crossword clue is the 4 plus 3 letter word NAME TAG
I've seen this crossword clue in The Guardian
N
A
M
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T
A
G
More clues leading to the result NAME TAG
- Guardian up for identifying marker
- Harry’s blocked by a police force wanting ID
- Identity badge of Spooner’s gentle horse
- Gate man verifies one’s identity.
- Label the Guardian revolutionary
- Security person turned over identification
- Proof of identity sentry looking over
- ID Spooner’s broken mustang?
- Call time on a good sign of identification
- A police force stops horse, which provides identification
Buddy explains!
The straight part
We know that "Proof of identity/Proof of identity" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case proof of identity/proof of identity = name tag.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.