IPA: /ˈkætɪˌkjuːmən/
KK: /ˈkætɪˌkjumən/
A person who is learning about the basic principles of Christianity, usually in preparation for baptism.
The church held a special class for catechumens to help them understand their faith better.
Catechumen → It is formed from "katechein" (Greek, meaning to instruct or teach) and the suffix "-men" (indicating a person). A catechumen is a person who is being instructed in the principles of the Christian faith, particularly before baptism.
Think of someone being 'instructed' ('katechein') in their faith — that's why a catechumen is someone learning about Christianity.