muff (muffs plural & 3rd person present) (muffing present participle) (muffed past tense & past participle )
1 verb If you muff something, you do it badly or you make a mistake while you are doing it, so that it is not successful.
INFORMAL He muffed his opening speech. V n
2 n-count A muff is a piece of fur or thick cloth shaped like a short hollow cylinder. You wear a muff on your hands to keep them warm in cold weather.