A Teachta Dála (Irish pronunciation: [ˈtʲaxtə ˈdɑːlə]), usually abbreviated as TD, is a member of Dáil Éireann, the lower house of the Oireachtas (the Irish Parliament). It is the equivalent of terms such as "Member of Parliament" (MP) or "deputy" used in other states. The official translation of the term is "Deputy to the Dáil", though a more literal translation is "Assembly Delegate". "Teachtaí Dála" is the plural form in Irish.

The term was first used to describe those Irish parliamentarians who were elected at the 1918 general election, and who, rather than attending the British House of Commons in London, to which they had been elected, assembled instead in Dublin's Mansion House on 21 January 1919 to create a new Irish parliament: the First Dáil Éireann. The term continued to be used after this First Dáil and was used to refer to later members of the Irish Republic's single chamber Dáil Éireann (or "Assembly of Ireland") (1919–1922), members of the Free State Dáil (1922–1937), and of the modern Dáil Éireann.