Mary, also referred to as The Virgin Mary, was a Human female that was born on the planet Earth in the 1st century BC. According to Christian tradition, Mary was the daughter of Saint Anne and the mother of Jesus Christ.
Mary was depicted in Leonardo da Vinci paintings The Virgin and Child with St. Anne as well as Adoration of the Magi, which were found among the relics in Kathryn Janeway's da Vinci holodeck program. (VOY: "Scorpion", "The Raven", "Scientific Method", "Concerning Flight")
In a ward of Sisters of Hope Infirmary, a hospital in 1893 San Francisco, there was a small statue of Mary. (TNG: "Time's Arrow, Part II")
In 2376, upon witnessing fellow hologram Maggie O'Halloran transform into a cow, Milo exclaimed, "Holy mother of God!" (VOY: "Spirit Folk")