shoulder knot

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Either of two detachable braided cords worn on each shoulder of the full-dress uniform of a commissioned officer.
• noun An ornamental knot of ribbon or lace formerly worn on the shoulder.

from The Century Dictionary.

• noun A knot of ribbon or of metal lace worn on the shoulder.
• noun An epaulet.
• noun A piece of jewelry made to wear on the shoulder, as a brooch or simple ornament: most generally a diamond pin set with many stones.
• noun One of certain noctuid moths: an English collectors' name. Hadena basilinea is the rustic shoulder-knot.