Catechism of the Catholic Church §1007 — excerpt
Death is the end of earthly life. Our lives are measured by time, in the course of which we change, grow old and, as with all living beings on earth, death seems like the normal end of life.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.