Tanistry was a system for passing on titles and lands. In this system the Tanist (Irish Tánaiste; Scottish Gaelic Tànaiste; Manx Tanishtagh) was the office of heir-apparent, or second-in-command, among the (royal) Gaelic patrilineal dynasties of Ireland, Scotland and Man, to succeed to the chieftainship or to the kingship. Origins The Tanist was chosen from among the heads of the roydammna or "righdamhna" (literally, those of kingly material) or alternatively among all males of th… (More on Tanistry)