When I use a word . . . . Coronership—a lexicographic puzzle

Coronership, the office of a coroner in England, dates back to at least the end of the 12th century, with the Articles of Eyre of 1194, instituted by Richard I. The word derives from the statute that referred to the new office: “Furthermore, a company of three soldiers and one cleric is to be elected in a suitable fashion as guardians of the pleas of the crown” or, in the original Latin, as recorded by the historian Roger of Hoveden, “Praeterea in quolibet comitatu eligantur tres milites et unus clericus custodes placitorum coronæ.” Although the original medieval Latin version of “coroner” was “coronarius,” it was later changed to “coronator,” from which the adjective “coronatorial,” used commonly throughout the 19th century, although less since then, derived. The current adjectival derivative of “coroner,” “coronial,” has also been widely in use since the start of the 19th century. However, in the Oxford English Dictionary “coronatorial” is marked as ”rare” and “coronial” is not included as a headword at all. Of all other major dictionaries, only Webster’s New International Dictionary of 1920 includes “coronatorial,” and none includes “coronial.” That needs to be rectified.