RI
See also: Appendix:Variations of "ri"
English
Proper noun
RI
- Initialism of Rhode Island, a state of the United States of America.
- Abbreviation of Riau, a province of Indonesia.
Noun
RI (plural RIs)
- Initialism of radioisotope.
Abbreviation
RI
- (monarchy) rex imperator (“king-emperor”) or regina imperatrix (“queen-empress”); the initials by which a British monarch signed documents after his or her name from 1877 until 1947.