A triple deity is a deity with three apparent forms that function as a singular whole. Such deities may sometimes be referred to as threefold, tripled, triplicate, tripartite, triune, triadic, or as a trinity. The number three has a long history of mythical associations and triple deities are common throughout world mythology. Carl Jung considered the arrangement of deities into triplets an archetype in the history of religion.

The Morrígan or Mórrígan, also known as Morrígu, is a figure from Irish mythology. The name is Mór-ríoghan in modern Irish before the spelling reform, and it has been translated as "great queen" or "phantom queen".