Wiktionary
protreptic
a. Serving to instruct; didactic n. A didactic speech, book etc
Usage examples of "protreptic".
At the transition point of the journey, where the Protreptic stopped accelerating, turned a half-somersault and pointed its engines at its destination to start deceleration, Quercer & Janath spent some time checking that Y'sul was still healing satisfactorily.