Diancécht,
Dían Cécht
[Irish, rolling quickly forward (?); swift power (?)]
Principal healing god or physician of the ancient Irish and ‘sage of leechcraft’ (i.e. medicine) for the Tuatha Dé Danann. Father of Étan (1) and Cian, thus grandfather of Lug Lámfhota. In Cath Maige Tuired [The (Second) Battle of Mag Tuired] Dian Cécht's powerful healing spring can restore every mortally wounded man, except for the decapitated. More memorably, he makes a wonderful silver arm and hand with moving fingers for the wounded Nuadu, who is afterwards called Nuadu Airgetlám [of the Silver Hand/Arm]. The arm is not sufficient, however, to qualify Nuadu for kingship. Later Dian Cécht's son Miach makes Nuadu an arm of flesh that allows him to ascend to power. In jealousy at his son's greater power, Dian Cécht then slays Miach. Dian Cécht is also jealous of his daughter Airmid, who has sought to classify all magical healing herbs; he disrupts her ordering. The hero Mac Cécht appears to be euhemerized from Dian Cécht.
Dian Cécht was known late into Christian times and his charms invoked at least until the 8th century. In modern folklore Dian Cécht's porridge is a cure for colds, sore throat, phlegm, and worms; it is made of hazel nuts, dandelion, woodsorrel, chickweed, and oatmeal.