TED-Ed

View full lesson: http://ed.ted.com/lessons/mysteries-of-vernacular-x-ray-jessica-oreck-and-rachael-teel The story of the word X-Ray is one of great thinkers. French philosopher Rene Descartes isolated the letters X, Y and Z to stand for unknowns, and centuries later, Wilhelm Röntgen discovered the X-ray, using the X for the unknown nature of the radiation. Jessica Oreck and Rachael Teel shed some light on the etymology of this modern marvel. Lesson by Jessica Oreck and Rachael Teel, animation by Jessica Oreck.