Distinguishing the difference between what a bracelet is and what an armlet is can enter into grey area. A bracelet worn at the ankle is simply called an anklet. But the word armlet is actually defined as something that sits on the upper arm.
Both are so similar in shape and relative size, that it can often be mistaken or either could be worn both as a bracelet and as an armlet. Some dictionaries define a bracelet as only pertaining to the wrist, while others say the wrist and arm. People sometimes push bracelets up the arm because they are so big and don’t want it to continuous move around.
In deconstructing what a bracelet is, a bracelet can simply be defined as an ornamental band or circlet fit around any part of the body. You could consider an armlet, ring, anklet, necklace, belt… as bracelets tailored for a specific part of the body.