That female feeding rook calls for some nuts (7)

'some nuts' is the definition.
(cashew is a kind of nut)

'that female feeding rook calls' is the wordplay.
'that female' becomes 'she' ('she' refers to a woman).
'feeding' indicates putting letters inside (one word is fed by another set of letters).
'rook calls' becomes 'caws' (I've seen this before).
'she' going into 'caws' is 'CASHEWS'.

'for' acts as a link.