Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.

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.