The heir apparent to a Celtic chief, typically the most vigorous adult of his kin, elected during the chief's lifetime.
- ‘The chief usually named the tanist while he was living, and the individual bore the title during the remaining lifetime of the chief.’
- ‘The clan organization consisted of the chief, the tanist, the chieftains, the captain, the daoin'-uaisle - the gentlemen, and the general body of the clan.’
- ‘While it was not the rule for the king to be killed by his tanist, it was not uncommon either.’
- ‘Following the tanist in the hierarchy of the clan is the commander or military leader.’
- ‘The tanist shall receive the ancient and honorable coronet of the Principality according to the traditions of the Principality.’
Mid 16th century: from Irish and Scottish Gaelic tánaiste, literally second in excellence.