Concentrating, joined old conservative inside (7)

I believe the answer is:

focused

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'concentrating joined old conservative inside' is the definition.
I can't tell whether this defines the answer.

'joined old conservative inside' is the wordplay.
'joined' becomes 'fused' (fused means joined together).
'old' becomes 'o' (abbreviation).
'conservative' becomes 'C' (UK political abbreviation).
'inside' is an insertion indicator.
'o'+'c'='oc'
'fused' enclosing 'oc' is 'FOCUSED'.

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(Other definitions for focused that I've seen before include "(Of light) brought to a point" , "not easily diverted" , "Concentrated on - like camera" .)

I've seen this clue in The Daily Express.

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