agraffe

noun3

1. •
   A decorated clasp consisting of a hook which fastens onto a ring, similar to hook and eye, used in armor or in ordinary clothing.

   • A young girl is about to join together on her left shoulder the chiton, which is fastened over the right shoulder by means of an agraffe. — 1884
2. •
   A brass fitting, screwed into a piano plate, that positions the strings vertically and laterally, and defines one end of the string's speaking length.
3. •
   A carved keystone, usually decorated with a mascaron or a corbel, often used in Classical architecture.