Rubrics are liturgical directions. The term comes from the fact that in medieval service books, such instructions were written in red (Lat. ruber), to distinguish them from the text of the service itself. Rubrics are found in service books, as well as in liturgical guides that focus exlusively on such instructions.
- F.L. Cross & E.A. Livingstone, eds., The Oxford Dictionary of the Christian Church, 2nd Ed. (Oxford: Oxford University Press, 1989), s.v. “Rubrics", p 1207.