Servant turning in during a meal (6)
I believe the answer is:
menial
'servant' is the definition.
(menial is a kind of servant)
'turning in during a meal' is the wordplay.
'turning' is a reversal indicator.
'during' means one lot of letters goes inside another.
'in' back-to-front is 'ni'.
'ni' put into 'meal' is 'MENIAL'.
(Other definitions for menial that I've seen before include "Domestic servant" , "Unskilled, degrading" , "(Suitable for) servant of low status" , "Humble - servant" , "A drudge" .)