Do you know ghouls from goblins and ghosts?
c.1300, "directions in religious services" (often in red writing), from Old French rubrique, rubriche "rubric, title" (13c.), from Latin rubrica "red ochre, red coloring matter," from ruber, from PIE root *rudhro- (see red). Meaning "title or heading of a book" is from early 15c. Related: Rubrical.