Gilla na nAingel Ó Caiside, Gaelic-Irish physician, died 1335.
Ó Caiside was one of the earliest recorded members of a brehon family who became hereditary physicians for the Kings of Fer Manach. The Annals of the Four Masters, sub anno 1335, record of him:
One of his recorded descendants was Tadhg Ó Caiside, who died 1450.