Word Unit: rim- (Latin: crack, chink)

Word Unit: ripari-, ripa-, rip-, riv- (Latin: ripa, river, stream; bank, river bank, shore)

Word Unit: rit-, ritual- (Latin: ritus, religious observance or ceremony; custom, usage)

Word Unit: Roads That Led to Rome, Part I, Section 1 (The Roads That Led to Rome by Victor W. Von Hagen)

Word Unit: Roads That Led to Rome, Part I, Section 2 (The Roads That Led to Rome by Victor W. Von Hagen)

Word Unit: Roads That Led to Rome: Index of Parts (when all roads led to Rome)

Word Unit: robor-, robust- (Latin: strengthening; to make stronger, to invigorate; strength)

Word Unit: Robot Origins and the Characteristics of Robots (a Czech word, robota meaning "serf" or "slave" or "forced work" which is now applied to any manufactured device that is capable of doing work ordinarily done by human beings)

Word Unit: Robot: Segway Toy (using Segway's balancing technology)

Word Unit: Robots and Robotics: A Directory or Index (links to topics about robots, robotic devices, and the science of robotics)

Word Unit: Robots: As Human Partners, Part 1 (helping to save military lives)

Word Unit: Robots: As Human Partners, Part 2 (robots performing mundane household tasks)

Word Unit: Robots: Humanoids (for robots, a new way of walking like humans)

Word Unit: Robots: Industrial Applications (robotics on the move)

Word Unit: Robots: With Feelings? (robots with the right touch)

Word Unit: rod-, ros- (Latin: gnaw, eat away; eaten away, gnawed off, consumed)

Word Unit: Roentgen Biography (Conrad Röntgen (Roentgen), Discoverer of X-rays)

Word Unit: roentgeno-, roentgen- + (German: radiation, "x-ray"; X-ray; 1896, translation of German X-strahl, from X, "algebraic symbol for an unknown quantity", + Strahl, "beam, ray")

Word Unit: rog-, roga-, -rogate, -rogation, -rogatory (Latin: ask, inquire, request, beg; propose)

Word Unit: roma- + (Latin: Rome)