bursas

plural of bursa

Any of the many small fluid-filled sacs located at the point where a muscle or tendon slides across bone. These sacs serve to reduce friction between the two moving surfaces.
A diverticulum on the cloaca of young birds, which serves as a lymphatic organ and as part of the immune system, but which atrophies as the bird ages.
Any of various pouch-like organs for storing semen prior to copulation in the male or for receiving semen in the female.
A parament about twelve inches square in which the folded corporal is kept in for reasons of reverence.