Under the 1937 Irish constitution, Bunreacht na hÉireann, the Oireachtas is made up of the President of Ireland and two houses, the lower house, Dáil Éireann (pronounced, dall air-inn translated as House of Representatives) and the upper house, Seanad Éireann (pronounced, sch-anad air-inn).
The term was also used to describe parliament in the previous constitution of the Irish Free State, enacted in 1922. It was made up of the King and two Houses, Dáil Éireann (translated as the Chamber of Deputies) and Seanad Éireann. Both the King and the Seanad were abolished by constitutional amendments in 1936, before the entire constitution was replaced by Bunreacht na hÉireann in 1937.
The term was not used under the 1919 Dáil Constitution, which simply provided for a single chamber parliament, also called Dáil Éireann, which was translated in that text as the Assembly of Ireland.
An oireachtas is also a hugely important kind of competition in Irish dance.