The most common and most likely answer to this crossword clue is the 6 letter word SIGNET
I've seen this crossword clue in The Times
S
I
G
N
E
T
More clues leading to the result SIGNET
- Retreating soldiers capture seal
- Ring number up after brief expression of weariness
- Ring up a number of soldiers
- A small seal is back with good catch
- Ring back a number of soldiers
- Band’s ‘Ugly Duckling’ on the radio
- Number of US soldiers in retreat making an impression
- Ring number of US soldiers up
- Small seal, or ugly duckling mentioned
- Sounding like baby bird, old seal
Buddy explains!

The straight part
We know that "seal" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case seal = signet.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 SIGNET mean?
SIGNET noun- An object (especially a ring) formerly used to impress a picture into the sealing wax of a document as a proof of its origin