1) Celtic mythology encompasses the folklore and legends of the Celtic peoples across Europe, particularly in regions like Ireland, Scotland, and Wales. It features deities like Morrigan, Cernunnos, and Brigid, and delves into themes of nature, magic, and the heroic exploits of legendary figures like Cu Chulainn.

2) The Atlantic Ocean is the second-largest ocean and is known for its strong ocean currents, including the Gulf Stream.

3) The role of the judiciary is to interpret laws, resolve disputes, and ensure justice in accordance with legal principles and the constitution. It serves as a check on the executive and legislative branches of government.

4) International relations encompass the study of relationships between nations, including diplomacy, treaties, and foreign policy. It examines the interactions and dynamics among different countries in the global arena.