muff up

English

Verb

muff up (third-person singular simple present muffs up, present participle muffing up, simple past and past participle muffed up)

1. To mess up; to botch
   • 1922, Agatha Christie, “Chapter 16”, in The Secret Adversary:

     "You're tying my hands," complained Tommy. "It's a very delicate affair, and the other fellow will muff it up as likely as not, and then where shall I be? I don't believe one of you has got an ounce of tact."