Ramora - this silvery fish (muggles call it the remora) has the power to anchor ships.

Ravenclaw - one of the four houses of Hogwarts School of Witchcraft and Wizardry.

Ravenclaw, Rowena - founder of Ravenclaw House

Red Cap - also called bloody cap or red comb, these are goblin-like creatures, small in stature (about four feet tall) but large in their capacity for bloodthirst. They exist in English and Scottish folklore. They look like old men of sturdy build and have long gray hair. Red is the color of their eyes and their caps, which they soak in the blood of their victims. This evil elf lives in or haunts castle ruins where bloody battles have taken place. He uses his walking stick, tipped with a metal spike, to beat and kill anyone lost in his territory. He also tosses boulders on travellers from high up in his tower. A red cap can be discouraged only by crosses, swords with a cross-like handle, or by reading aloud from the Bible, which makes him shriek and disappear, leaving behind only one of his hideous, protruding teeth, if the vanquisher desires such an ugly souvenir.

Reducio (Spell) - used to reduce the size of an object.

Reducto (Spell) - the Reducto Curse can blast objects out of the way or blast a passage through something solid.

Re'em - very rare giant oxen with golden hides, inhabiting wild regions of North America and the far east. The blood of the re'em, which is difficult to obtain, gives the drinker immense strength.

Relashio (Spell) - a spell that casts fiery sparks. Underwater, it shoots a jet of boiling water.

Reparo (Spell) - repairing something that has been broken.

Rictusempra (Spell) - a tickling charm that makes people laugh uncontrollably.

Riddikulus (Spell) - the spell used to disarm the Boggart by turning it into something silly, or ridiculous.

Romanian Longhorn (Dragons) - the dark green scales of this dragon contrast with its long golden horns. It uses these horns to gore its prey before roasting its dinner. Powdered, these glittering horns are in high demand as a potion ingredient -- so high that the longhorn is an endangered species. They are being bred to try and increase their numbers.

Rosewood (Plant) - a "wand tree". Fleur Delacour has a wand made of rosewood.

Runes - meaning "mystery" or "secret" in Danish. Any character or symbol from the earliest known Germanic alphabet, runes appeared around the third century A.D., and were in use until displaced by Latin more than a millenia later. They were used in the British Isles, the island of Iceland, and Scandinavia.

Runespoor - a three-headed snake from the African nation of Burkina Faso. Runespoor grow to six or seven feet. They are bright orange with black stripes.

The three heads each serve a different function. The left (as viewed when facing this interesting reptile) is the planner, deciding what to do and where to go. The middle head is the dreamer of the trio. The right critiques the other two. The fangs of the right head are very venomous. Since the heads have a tendency to attack each other, the runespoor rarely grows old. A common sight is one with a missing right head, since the other two gang up on it to bite it off.

This creature produces eggs through its mouths, a unique trait amongst magical beasts. These eggs are used in potions which stimulate mental agility.