Riddermark means "land of the riders", derived from the Old English compound Riddena-mearc ("riders' mark" or "The Territory of the Knights"). Mark here is used in the sense of "borderland, especially one serving as a defence of the inner lands of a realm".
- Wayne G. Hammond and Christina Scull (eds), The Lord of the Rings: A Reader's Companion, p. 248
- Jason Fisher, "Horns of Dawn: The Tradition of Alliterative Verse in Rohan", in Middle-earth Minstrel: Essays on Music in Tolkien (ed. Bradford Lee Eden), p. 21 (note 18)
- Greg Harvey, The Origins of Tolkien's Middle-earth for Dummies, "The Rohirrim"
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Peoples of Middle-earth, "II. The Appendix on Languages", p. 53
- Wayne G. Hammond and Christina Scull (2006), The J.R.R. Tolkien Companion and Guide: Reader's Guide, "Morris, William", p. 600