Boy cut a long boiled sausage (7)
I believe the answer is:
bologna
'sausage' is the definition.
(bologna is a kind of sausage)
'boy cut a long boiled' is the wordplay.
'cut' means to remove the last letter.
'boiled' is an anagram indicator.
'boy' with its final letter removed is 'bo'.
'a'+'long'='along'
'along' anagrammed gives 'logna'.
'bo'+'logna'='BOLOGNA'
(Other definitions for bologna that I've seen before include "Italian city - smoked sausage" , "Capital of Emilia-Romagna" , "Italian province" , "North Italian university city" .)