Catechism of the Catholic Church §752 — excerpt
In Christian usage, the word "church" designates the liturgical assembly, but also the local community or the whole universal community of believers. These three meanings are inseparable.
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.
Also cites: Cf.1 Cor 11:18