The most common and most likely answer to this crossword clue is the 5 letter word SHIRK
S
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More clues leading to the result SHIRK
Buddy explains!

The straight part
We know that "Soldier" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case soldier = shirk.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 SHIRK mean?
SHIRK noun- One who shirks, who avoids a duty or responsibility.
- To avoid, especially a duty, responsibility, etc.; to stay away from.
- To evade an obligation; to avoid the performance of duty, as by running away.
- To procure by petty fraud and trickery; to obtain by mean solicitation.
- The unforgivable sin of idolatry.