Browse the Concise Encyclopedia
- rice
- rice university
- richardson, samuel
- richter scale
- rickets
- rickettsia
- riddle
- rif
- rif, el-
- rifle
- rift valley
- riga, gulf of
- riga, treaty of
- right
- right whale
- right-to-work law
- rigveda
- rikken seiyukai
- rinderpest
- ring
- ring of fire
- ringling brothers
- rings
- ringworm
- río de la plata, viceroyalty of the
- río de oro
- rio treaty
- rip current
- riparian right
- ripple mark
- risc
- risk
- risorgimento
- ritalin
- river
- river blindness
- riviera
- rko radio pictures, inc.
- rna
- roach
- road
- roadrunner
- roasting
- rob roy
- robber fly
- robeson channel
- robin
- robin hood
- robot
- robotics
- roca, cape
- rocaille
- roche limit
- rock
- rock art
- rock crystal
- rock glacier
- rock music
- rockefeller center
- rockefeller foundation
- rocket
- rockfish
- rocky mountain national park
- rocky mountain spotted fever
- rocky mountains
- rococo style
- rodent
- rodeo
- roe deer
- roe v. wade
- rolfe, john
- rolle's theorem
- roller bearing
- roller-skating
- rolling
- rolling stones
- rolls-royce plc
- rom
- roman
- roman à clef
- roman catholicism
- roman curia
- roman de la rose
- roman law
- roman mythology
- roman numerals
- roman question
- roman religion
- roman republic and empire
- romance
- romance languages
- romanesque architecture
- romanesque art
- romanian language
- romanov dynasty
- romanticism
- romany language
- rome, march on
- rome, treaties of
- romulus and remus