Catechism of the Catholic Church §2284 — excerpt
Scandal is an attitude or behavior which leads another to do evil. the person who gives scandal becomes his neighbor's tempter. He damages virtue and integrity; he may even draw his brother into spiritual death.
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.