noun
Catholic catechism
Refers specifically to the catechism of the Catholic Church, a summary of doctrine often used for instruction.
公教要理を学ぶために教会に通っている。
I attend church to study the Catholic catechism.
Compound of 公教 (Catholicism) and 要理 (essential doctrine). The exact historical derivation is uncertain, but the term is conventionally used for the Catholic catechism.