Direct fellow getting alien some restraint (14)

I believe the answer is:

straightjacket

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'some restraint' is the definition.
(thesaurus)

'direct fellow getting alien' is the wordplay.
'direct' becomes 'straight' (similar in meaning).
'fellow getting alien' becomes 'jacket' (I can't justify this - if you can you should believe this answer much more).
'straight'+'jacket'='STRAIGHTJACKET'

Can you help me to learn more?

I've seen this clue in The Daily Express.

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