A solemnity is, in the liturgical calendar of the Roman Rite, a feast day of the highest rank celebrating a mystery of faith such as the Trinity, an event in the life of Jesus, his mother Mary, or another important saint. The observance begins with the vigil on the evening before the actual date of the feast. 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 inscribed in the General Roman Calendar and which are therefore observed throughout the Latin Church are indicated in the following list.
|Date||Solemnity||Notes about date|
|1 January||Blessed Virgin Mary, Mother of God||Octave of Christmas, Circumcision of the Lord, New Year's Day|
|6 January||Epiphany of the Lord||Where not a holy day of obligation, transferred to the Sunday between 2 January and 8 January, inclusive|
|19 March||Saint Joseph, spouse of the Blessed Virgin Mary||If the Solemnity of Saint Joseph, where observed as a holy day of obligation, coincides with Palm Sunday, it is, by exception to the general rule, anticipated to Saturday 18 March; where not observed as a holy day of obligation, the episcopal conference may transfer it to a date outside Lent.|
|25 March||Annunciation of the Lord||If the Solemnity of the Annunciation of the Lord falls on any day of Holy Week, it is always transferred to the Monday after the Second Sunday of Easter (30 March to 9 April), rather than, in accordance with the general rule, to the next day not occupied by a celebration with at least the rank of feast|
|(22 March to 25 April)||Resurrection of the Lord (Easter)||Concludes the Paschal Triduum that commemorates also the last supper, passion, death, burial and resurrection of Christ. See Computus for date computation. Begins Octave of Easter, eight consecutive days celebrated as one continuous solemnity, ending 29 March to 2 May). See also Resurrection of Jesus.|
|Thursday after the Sixth Sunday of Easter (40th day of Eastertide - 30 April to 3 June)||Ascension of the Lord||If not a holy day of obligation, transferred to replace the Seventh Sunday of Easter (3 May to 6 June)|
|50th day of Eastertide (10 May to 13 June)||Pentecost||(Whitsunday); always on a Sunday|
|Sunday after Pentecost (17 May to 20 June)||Trinity Sunday|
|Thursday after Trinity Sunday (21 May to 24 June)||Most Holy Body and Blood of Christ||"Corpus Christi"; in some dioceses, celebrated on the following Sunday (24 May to 27 June).|
|Friday (8 days after Corpus Christi Thursday, 5 days after Corpus Christi Sunday) (29 May to 2 July)||Most Sacred Heart of Jesus|
|24 June||Nativity of Saint John the Baptist|
|29 June||Saints Peter and Paul|
|15 August||Assumption of Mary|
|1 November||All Saints|
|Last Sunday before Advent (20–26 November)||Our Lord Jesus Christ, King of the Universe||Replaces 34th Sunday in Ordinary Time|
|8 December||Immaculate Conception of the Blessed Virgin Mary|
|25 December||Nativity of the Lord (Christmas)||everywhere a holy day of obligation; see also Nativity of Jesus|