section_path: History/Origins and etymology
section_name: Origins and etymology
paragraph_text: Origins and etymology
  
  The words Taoiseach and Tánaiste (deputy prime minister) are both from the Irish language and of ancient origin. The Taoiseach is described in the Constitution of Ireland as "the head of the Government or Prime Minister", its literal translation is ' chieftain ' or ' leader '. Although Éamon de Valera, who introduced the title in 1937, was a democratic politician who had in the past associated with paramilitaries, some have remarked that the meaning ' leader ' in 1937 made the title similar to the titles of fascist dictators of the time, such as Führer (for Adolf Hitler), Duce (for Benito Mussolini) and Caudillo (for Francisco Franco). Tánaiste, in turn, refers to the system of tanistry, the Gaelic system of succession whereby a leader would appoint an heir apparent while still living.
  
  In Scottish Gaelic, tòiseach translates as ' clan chief' and both words originally had similar meanings in the Gaelic languages of Scotland and Ireland. The related Welsh language word tywysog (current meaning: 'prince') has a similar origin and meaning. It is hypothesised that both derive ultimately from the proto-Celtic * towissākos 'chieftain, leader'.
  
  The plural of taoiseach is taoisigh (Northern and Western Irish:, Southern:).
  
  Although the Irish form An Taoiseach is sometimes used in English instead of 'the Taoiseach', the English version of the Constitution states that they "shall be called … the Taoiseach".