Catechism of the Catholic Church §2395 — excerpt
Chastity means the integration of sexuality within the person. It includes an apprenticeship in self-mastery.
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.