Soldiers run away from restraints (7)

I believe the answer is:

legions

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'restraints' is the definition.
Although both the answer and definition are plural nouns, I don't see how one could define the other.

'soldiers run away' is the wordplay.
'soldiers' becomes 'legion' (I've seen this before).
'run away' becomes 's' (I can't justify this - if you can you should believe this answer much more).
'legion'+'s'='LEGIONS'

'from' acts as a link.

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