do someone's business

do someone's business (third-person singular simple present does someone's business, present participle doing someone's business, simple past did someone's business, past participle done someone's business)

1. (dated) To ruin someone; to do for.
   • 1702, George Farquhar, The Inconstant, or the Way to Win Him:

     I'll spoil his wandering, I'll him. I'll do his business that way, never fear.

• do one's business