Some frantic person opposing something (4)

I believe the answer is:

anti

'person opposing something' is the definition.

'some frantic' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'ANTI' is hidden within 'frantic'.

(Other definitions for anti that I've seen before include "[NO MAN]" , "Against, informally" , "An opponent - opposed to party policy, etc" , "Not favouring" , "on the other side" .)

I've seen this clue in The Times.

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