The directions and rules for the conduct of service, formerly written or printed in red; hence, also, an ecclesiastical or episcopal injunction; usually in the plural. All the clergy in England solemnly pledge themselves to observe the rubrics. (hook)
Hence, that which is established or settled, as by authority; a thing definitely settled or fixed. Nay, as a duty, it had no place or rubric in human conceptions before christianity. (De Quincey) category, class, classification under the rubric of, (See def. (b)) in the category of
Origin: OE. Rubriche, OF. Rubriche, F. Rubrique (cf. It. Rubrica), fr. L. Rubrica red earth for colouring, red chalk, the title of a law (because written in red), fr. Ruber = red. See red.