Temporarily, then, on going into the force (3,3,5)

I believe the answer is:

for the nonce

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'temporarily' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'then on going into the force' is the wordplay.
'going into' indicates putting letters inside.
'then'+'on'='thenon'
'thenon' placed within 'force' is 'FOR THE NONCE'.

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