Immaculate Conception: usual reference is in relationship to the birth of Jesus who had no earthly father who impregnated Mother Mary, but rather was a result of the Holy Spirit's impregnation. Edgar Cayce's channelings of the Universal Mind state that Mother Mary was born of the immaculate conception as well! Impregnation by the Spirit of God
The belief that before the birth of Mary (the mother of Jesus) was born, she was preserved from original sin at the time of her conception, circa 20 BCE. It is widely but incorrectly believed to refer to Jesus' conception, circa 5 to 8 BCE.
Roman Catholic holy day first celebrated in 1854
(Christianity) the Roman Catholic doctrine that the Virgin Mary was conceived without any stain of original sin
Catholics believe that Mary, to be a fitting mother for Christ, was herself born free of sin by immaculate conception. The Feast of the Immaculate Conception is celebrated by the Roman Catholic Church on the 8 December as a holy day of obligation, commemorating the immaculate conception of Mary.
In the Roman Catholic Church, the doctrine that the Virgin Mary was conceived in her mother's womb without the stain of original sin: distinguished from Virgin Birth
the distinct privilege of the Blessed Virgin, Mary, who, through the merits of her Divine Son, was conceived in her mother's womb without the guilt or stain of "original sin" and has been a dogma (see dogma above) of the Catholic Church since 1854
The teaching that Mary was conceived without original sin.
(Roman Catholic) Day of celebrating the belief that Mary, mother of Jesus, was preserved from original sin all of her life; Observed as a day of obligation with required church attendance
Catholic dogma concerning Mary and the name of a feast in her honor celebrated Dec. 8. It refers to the Catholic belief that Mary was without sin from the moment she was conceived.
Doctrine of the Roman Catholic Church that Mary conceived of Jesus by the Holy Spirit, but remained free of original sin.