Generally gutted sailor must be spinning (8)
I believe the answer is:
gyrating
'spinning' is the definition.
('gyrate' can be a synonym of 'spin')
'generally gutted sailor' is the wordplay.
'gutted' says to hollow out the word (remove centre letters) (to gut something is to remove its insides).
'sailor' becomes 'rating' (British term for a naval enlisted man).
'generally' with its middle taken out is 'gy'.
'gy'+'rating'='GYRATING'
'must be' is the link.
(Other definitions for gyrating that I've seen before include "Spinning round" , "Whirling" , "Moving with a circular or spiralling motion" , "Revolving, moving around in circles" , "Circling, spiralling" .)