The Latin Tempus Per Annum ("time throughout the year") is rendered into English as "Ordinary Time." Many sources, online and in print, suggest that Ordinary Time gets its name from the word ordinal, meaning "numbered," since the Sundays of Ordinary Time, as in other seasons, are expressed numerically. However, others suggest the etymology of "Ordinary Time" is related to our word "ordinary" (which itself has a connotation of time and order, derived from the Latin word ordo). Ordinary Time occurs outside of other liturgical time periods, periods in which specific aspects of the mystery of Christ are celebrated. According to The General Norms for the Liturgical Year and the Calendar, the days of Ordinary Time, especially the Sundays, "are devoted to the mystery of Christ in all its aspects."
Ordinary time does not need to be "ordinary," and is not meant to mean that somehow we get a break from the Liturgical Year. The opposite is true: Ordinary Time celebrates "the mystery of Christ in all its aspects." Many important liturgical celebrations fall during Ordinary Time, including, Trinity, Corpus Christi, All Saints, the Assumption of Mary, and Christ the King.
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