The most common and most likely answer to this crossword clue is the 7 letter word PAROLED
I've seen this crossword clue in The Guardian
P
A
R
O
L
E
D
Buddy explains!
The straight part
We know that "Solder" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case solder = paroled.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 PAROLED mean?
PAROLED verb- To release (a prisoner) on the understanding that s/he checks in regularly and obeys the law.