Catechism of the Catholic Church §990 — excerpt
The term "flesh" refers to man in his state of weakness and mortality. The "resurrection of the flesh" (the literal formulation of the Apostles' Creed) means not only that the immortal soul will live on after death, but that even our "mortal body" will come to life again.
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.