Bloodbath (7)
I believe the answer is:
carnage
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bloodbath</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for carnage that I've seen before include "'Massacre, slaughter (7)'" , "Indiscriminate slaughter" , "Mass killing" , "Blood bath" , "Mayhem" .)