Affair, matter (7)
I believe the answer is:
shebang
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">affair</span>' is the first definition.<br/ ><span class="explanation-format__explanation">('shebang' can informally refer to a matter or situ)</span><br/ ><br/ >'<span class="explanation-format__original">matter</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(shebang means any matter or situation)</span><br/ ><br/ ></span>
(Other definitions for shebang that I've seen before include "circumstances" , "The whole ___ (entirely)" , "Lot" , "business" , "Matter" .)