Lewis Short
(adj.adv.) : praeceptīvus, a, um, adj.praecipio
* Preceptive, didactic (post-Aug.): pars philosophiae, quam Graeci παραινετικήν vocant, nos praeceptivam dicimus, Sen. Ep. 95, 1: portemus praeceptivo modo dicens,in the preceptive, hortatory mode,Tert. Res. Carn. 49; Ambros. Vid. 12, 73; id. in Luc. 6, 90.—Hence, adv.: praeceptīvē, preceptively, didactically (eccl. Lat.): portemus inquit, non portabimus, praeceptive, non promissive,Tert. adv. Marc. 5, 10.
Charlton T. Lewis, Charles Short, A Latin Dictionary