Ecclesiastical. a person under instruction in the rudiments of Christianity, as in the early church; a neophyte.
2.
a person being taught the elementary facts, principles, etc., of any subject.
Origin: 1325–75; < Late Latincatēchūmenus < Greekkatēchoúmenos (one who is) being taught orally, equivalent to katēche-, stem of katēcheîn to teach orally (see catechist) + -omenos middle present participle suffix; replacing Middle Englishcathecumyn < Middle Frenchcathecumine < Late Latin, as above
"new convert," 15c., from Fr. catechumène, from L. catechumenus, from Gk. katekhoumenos "one being instructed," passive prp. of katekhein (see catechesis).