What is aiguilette?

Answer 1

An aiguillette is an ornamental braided cord most often worn on uniforms but may also be observed on other costumes such as academic dress, where it will denote an honor. Originally, the word "aiguillette" referred to the lacing used to fasten plate armour together and particularly to support the arm defences. As such, a knot or loop arrangement was used which sometimes hung down from the shoulder.