A nobleman’s sword would normally be kept in an elaborately decorated sheath called a scabbard. Mercutio insults Tybalt by referring to his scabbard as a pilcher; a pilch is a cheap leather covering. He then paints an image of Tybalt having to pull his sword out by its ears, as if the sword were cowardly and he has difficulty getting it to come out to fight. He then warns Tybalt to hurry up or he’ll be bashed about his ears.