The term pomander arose during the Middle Ages from the French pomme d’ambre and referred to an aromatic ball made of ambergris, civet, musk, dried flowers, spices and scented oils. In time, the term became interchangeable with the containers into which these scented substances were kept.
The prophylactic function of scent was very important throughout the Middles ages and the Renaissance. Inhaling the aroma of specific spices and herbs, or simply carrying them on your person as a talisman, was thought to cure or prevent serious illness.
A sponge soaked in a sweet smelling solution, possibly rose water, would have been secreted behind the face of the skull, so that the scent could escape through the eyes, nose and mouth. The skull would also have acted as a memento mori to its owner, a pertinent reminder of the preciousness of life when challenged by death and disease.