Step 1 : Introduction to the question "Which word is used in international radio communications to denote the letter "R"?"
The code word for "R" is Romeo. The International Civil Aviation Organization (ICAO) assigned code words acrophonically to the letters of the English alphabet, so that critical combinations of letters can be pronounced and understood by radio or telephone regardless of language barriers or the quality of the communication channel. The 26 code words in the NATO phonetic alphabet are as follows: Alfa, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, and Zulu.