Ordinary Time continues until the beginning of the Season of Lent
Because the term ordinary in English most often means something that's not special or distinctive, many people think that Ordinary Time refers to parts of the calendar of the Catholic Church that are unimportant. Even though the season of Ordinary Time makes up most of the liturgical year in the Catholic Church, the fact that Ordinary Time refers to those periods that fall outside of the major liturgical seasons reinforces this impression. Yet Ordinary Time is far from unimportant or uninteresting.
Why Is Ordinary Time Called Ordinary?
Ordinary Time is called "ordinary" not because it is common but simply because the weeks of Ordinary Time are numbered. The Latin word ordinalis, which refers to numbers in a series, stems from the Latin word ordo, from which we get the English word order. Thus, the numbered weeks of Ordinary Time in fact represent the ordered life of the Church—the period in which we live our lives neither in feasting (as in the Christmas and Easter seasons) or in more severe penance (as in Advent and Lent), but in watchfulness and expectation of the Second Coming of Christ.