 Unlike feast days of the rank of feast (other than feasts of the Lord) or those of the rank of memorial, solemnities replace the celebration of Sundays outside Advent, Lent, and Easter (those in Ordinary Time).The word comes from postclassical Latin "sollemnitas", meaning a solemnity, festival, celebration of a day.The solemnities of Nativity of the Lord, the Epiphany, the Ascension, and Pentecost are outranked only by the Paschal Triduum.