RH, Rh, rH, or rh can stand for:
- Riemann hypothesis, an important unsolved problem in mathematics
- Ryan's Hope, a soap opera
- Rhesus factor, a classification to describe blood types in humans
- Rhodium, a chemical element
- Republic Express Airlines (IATA airline designator)
- Reinhard Heydrich, a chief of the Reich Security Main Office, Nazi Germany
- Rh (digraph)
- Red Hat, a GNU/Linux operating system
- Restoration Hardware, an American furniture chain of home furnishings, hardware, and outdoor and garden products
- Robin Hood, a heroic outlaw in English folklore
- The RH postal area in the United Kingdom Royal Mail postcode system
- Rolf Harris, Australian entertainer
- Rumbling Hearts, an anime
- Rubeus Hagrid, a character in the Harry Potter series
- Releasing hormone
- Rush hour, the two parts of the day with busy traffic caused by commuting
- Rush Hour (film series)
- Reproductive health
- Rydberg Constant, the Rydberg Constant for Hydrogen
- The Right Honourable
- Radiohead, an English alternative rock, electronica and experimental music band
- Ron Howard, an actor
- Robert Heinlein, an author
- Relative humidity, the amount of water vapor that exists in a gaseous mixture of air and water vapor
- Royal Hospital (disambiguation)
Douglas Harper's Etymology Dictionary
Usage examples of "rh".
I guess Rhes will also stay to supervise the settling of the city Pyrrans with his people.
He had planned to be first out, but Rhes happened to knock against him as Kerk came up so that the gray-haired Pyrran slipped by and leaped to the ground.
Another arrow flashed toward them and Rhes stepped aside so that it missed him.
The next move will be to unite the tribes here, with Kerk in control or close to it, to welcome Rhes when he sails north with his trade goods.
The women could not ride with them, and eight men had gone to the lowlands with Rhes, while the remainder were on guard duty at the ship.
A man with an ugly black beard, wearing the uniform of a freelance soldier, entered, and Rhes flexed his fingers and stepped forward.
By later afternoon they entered the city, and Rhes threw a boy a small coin to show them the way to the palace.