the business end
the business end (of something)
The functional part of an instrument, tool, or other object. These kids are reckless on the ice, so watch that you don't get hit with the business end of a hockey stick. My dad swung at the intruding squirrel with the business end of a broom.
the business endthe part of a tool, weapon, etc. that carries out the object's particular function. informal
1936 Richmal Crompton Sweet William The business end of a geometrical compass was jabbed into Douglas's arm.