| Riñihue Lake | Lago Riñihue |
| RK Zagreb | RK Zagreb |
| RKO Pictures | RKO Pictures |
| RLC circuit | Circuito resonante |
| RLE | Run-length encoding |
| Rlogin | Rlogin |
| RMI-IIOP | RMI-IIOP |
| RMS Aquitania | Aquitania |
| RMS Britannic | HMHS Britannic |
| RMS Carpathia | RMS Carpathia |
| RMS Lusitania | RMS Lusitania |
| RMS Mauretania | RMS Mauretania |
| RMS Niagara | Niágara |
| RMS Olympic | RMS Olympic |
| RMS Queen Mary | Queen Mary |
| RMS Titanic | RMS Titanic |
| RMVB | RMVB |
| Rn | Radón |
| RNA | ácido ribonucleico |
| RNA interference | Ribointerferencia |
| RNA polymerase | ARN polimerasa |
| RNA virus | Virus ARN |
| RNA world hypothesis | Hipótesis del mundo de ARN |
| RNB | RNB |
| Ro ro ship | Transbordador |
| Ro ro vessel | Transbordador |
| roach | cucaracha |
| road | calle |
| road accident | accidente de tráfico |
| Road bicycle racing | Ciclismo |
| road map | hoja de ruta |
| road metal | grava |
| road network | red de carreteras |
| Road of Bones | Río Kolyma |
| Road of Life | Camino de la Vida |
| Road of the Seven Lakes | Camino de los Siete Lagos |
| road roller | apisonadora |
| road safety | seguridad en carretera |
| Road safety camera | Radar de tráfico |
| road salt | sal para deshielo de carreteras |
| road sign | señal de tráfico |
| road sweeper | barrendero |
| road tax | impuesto de carreteras |
| road test | prueba de tráfico |
| Road to Perdition | Camino a la perdición |
| road to success | camino hacia el éxito |
| road traffic | tráfico |
| road where stopping is prohibited | vía de emergencia |
| road worker | peón caminero |
| road-metal | cascajo |
| Road-rule enforcement camera | Radar de tráfico |
| roadability | estabilidad |
| roadbed | firme de carretera |
| roadblock | barricada |
| roadrunner | correcaminos |
| Roadrunner Records | Roadrunner Records |
| Roads in Portugal | Plano Rodoviário Nacional |
| roadside | borde de la carretera |
| roadside bomb | bomba caminera |
| roadside hawk | gavilán pollero |
| roadstead | fondeadero |
| roadster | coche de dos plazas |
| roadway | calzada |
| Roadworks | La obra |
| roadworthy | en condiciones de manejo |
| Roald Amundsen | Roald Amundsen |
| Roald Dahl | Roald Dahl |
| Roald Hoffmann | Roald Hoffmann |
| Roald Sagdeev | Roald Sagdeev |
| roam | rondar |
| roaming | itinerancia |
| roan | roano |
| Roanne | Roanne |
| roar | gritar |
| roar with laughter | morirse de risa |
| roaring | rugiente |
| roaring drunk | borracho |
| roaring success | éxito clamoroso |
| Roaring Twenties | Felices Años Veinte |
| roast | tostar |
| roast beef | rosbif |
| roasted | asado |
| roaster | asador |
| roasting | reprimenda |
| roasting pan | molde asador |
| rob | robar |
| Rob Bourdon | Rob Bourdon |
| Rob Halford | Rob Halford |
| Rob Levin | Rob Levin |
| rob of | quitar |
| Rob Pike | Rob Pike |
| Rob Van Dam | Rob Van Dam |
| Rob Zombie | Rob Zombie |
