Alienate some forest rangers (8)

I believe the answer is:

estrange

'alienate' is the definition.
(I know that alienate can be written as estrange)

'some forest rangers' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'ESTRANGE' is hidden in the letters of 'forest rangers'.

(Other definitions for estrange that I've seen before include "turn away?" , "Make enemy of sergeant" , "Alienate -- sergeant (anag)" , "As Regent (anag.)" , "separate" .)

I've seen this clue in the Sydney Morning Herald.

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