Bother! Inn sauce is spilt! (8)
I believe the answer is:
nuisance
'bother' is the definition.
(synonyms)
'inn sauce is spilt' is the wordplay.
'is spilt' is an anagram indicator.
'inn'+'sauce'='innsauce'
'innsauce' is an anagram of 'NUISANCE'.
(Other definitions for nuisance that I've seen before include "Trouble" , "Annoying or troublesome person or thing" , "See 16" , "Something which annoys" , "Bothersome pest" .)