A reference to the ability of a skilled fencer who could stab his opponent in any silk button of a shirt in myShakespeare's Romeo and Juliet, At 2, Scene 4.
Mercutio
in your bosom. The very butcher of a silk button, a duelist,
Mercutio mocks Tybalt by calling him “the very butcher of a silk button.” This is a reference to the most famous fencer of Shakespeare’s day, who boasted that he could stab his opponent in whichever shirt button he chose.