Lady Day

Also known as

  • Dies Mariae Deiparae
  • Day of Mary Mother of God


A title still commonly used in Ireland and elsewhere for the feast of the Assumption, 15 August. “Day of Mary Mother of God” is the primitive title for the feast. The old Armenian calendar (5th century) carried it for the date corresponding to 15 August under the title of the “Annunciation of the Mother of God” referring to the decree of the Council of Ephesus (c.431) which declared as a dogma of faith that Mary was truly the Mother of God.

MLA Citation

  • “Lady Day”. New Catholic Dictionary. CatholicSaints.Info. 23 September 2013. Web. 24 July 2016. <>