Servant in upset during dinner, perhaps (6)
I believe the answer is:
menial
'servant' is the definition.
(menial is a kind of servant)
'in upset during dinner perhaps' is the wordplay.
'upset' indicates anagramming the letters.
'during' is an insertion indicator.
'dinner perhaps' becomes 'meal' (dinner is a kind of meal).
'in' is an anagram of 'ni'.
'ni' inserted within 'meal' is 'MENIAL'.
(Other definitions for menial that I've seen before include "Humble - servant" , "Requiring little skill; lacking prestige" , "(Of job) low in prestige" , "Servile of lowly" , "'Humble, lowly, work say (6)'" .)