16O'Kelly, Michael. "Excavations and Experiments in Ancient Irish Cooking-Places." The Journal of the Royal Society of Antiquaries of Ireland 84.2 (1954): 138-39.
O'Kelly here translates fulacht fiadh as "cooking-place of deer," "cooking-place of game," or "cooking-place of the wild [outdoors]." His earliest source for this is the Medieval etymology Cormac's Glossary. There are some  4,500 fulacht fiadh in Ireland, with 2,000 found in Co. Cork. The stone walkway connecting the fulacht fiadh to the conjoined huts would have been required by the marshy landscape.