Etymology

From Swedish catechismus, German Katechismus, or directly from Late Latin catechismus, from Ancient Greek *κατηχισμός ‎(katēkhismós, “katēkhismos”), from κατηχίζω ‎(katēkhízō, “to catechize”), a later extended form of κατηχέω ‎(katēkhéō, “to catechize, instruct, teach by word of mouth”), from κατά ‎(katá, “down”) + ἠχέω ‎(ēkhéō, “to sound, to resound”).