A cover girl will (5)

I believe the answer is:

shell

'a cover' is the definition.
(shell is a kind of cover)

'girl will' is the wordplay.
'girl' becomes 'she'.
'will' becomes 'll'.
'she'+'ll'='SHELL'

(Other definitions for shell that I've seen before include "See 18" , "Protective outer case" , "Hard outer case" , "Protective outer casing" , "Petrol" .)

I've seen this clue in The Telegraph.

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