"Virtually every encyclopedia or textbook etymology of the word "robot" mentions the play R.U.R. Although the immediate worldwide success of the play immediately popularized the word (supplanting the earlier "automaton"), it was actually not Karel Capek but his brother Josef, also a respected Czech writer, who coined the word. The Czech word robota means "drudgery" or "servitude"; a robotnik is a peasant or serf. Although the term today conjures up images of clanking metal contraptions, Capek's Robots (always capitalized) are more accurately the product of what we would now call genetic engineering. The play describes of "kneading troughs" and "vats" for processing a chemical substitute for protoplasm, and a "stamping mill" for forming Robot bodies."
Short article on Capek's play Rossum's Universal Robots