Slaughterhouse (8)
I believe the answer is:
abattoir
'slaughterhouse' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for abattoir that I've seen before include "I tar boat (anag)" , "shambles once" , "It might make a killing" , "building where blood is shed" , "Slaughterhouse for animals" .)