A small circle borne as a charge in coats of arms.

annulet is a small ring, it is beleived that is it derived from the links composing chain armour. It is of frequent occurrence as a charge, and generally more than one appear: the two annulets are often linked in fess, or embraced; or they may be conjunct. Three may in like manner be interlaced in triangle. When three rings are interlaced the expression gimbal rings is sometimes used, and when more, they form a chain.
The single annulet is used in the mark of cadency, assigned to the fifth son.

In the Coat of Arms for Jean de Coaraze dating back to 1354 they used annulets.

This shield is described as:
Quarterly, I and IV, Gules, an Annulet Argent (Coaraze), II and III, Or, two Cows passant in pale Gules, horned, belled and hooved Azure