Mothballed like former army officer (3,2,10)
I believe the answer is:
out of commission
'mothballed like former army' is the definition.
The answer and definition are different parts of speech. However, past participle verbs and adjectives can sometimes define each other.
'officer' is the wordplay.
I cannot quite understand how this works, but
'officer' could be 'co' (Commanding Officer abbreviation) and 'co' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for out of commission that I've seen before include "Unable to work normally" , "Bust" , "removed from body?" , "Where agent usually gets money from" , "Not able to work" .)