About

Roger that dates back to US radio communication as early as 1941, based on then-use of the given name Roger in the US military phonetic alphabet for the word for the letter R. Here, the Roger stands for the initial R in “(Message) received.”

To indicate a message had been heard and understood—that is, received—a service-person would answer Roger, later expanded to Roger that, with that referring to the message. In military slang, the phrase Roger wilco conveyed the recipient received the message and will comply with its orders, shortened to wilco.

Roger was brought into the spotlight in part due to public broadcasts of NASA’s Apollo missions in the 1960s. Soon after, Roger that entered the popular lexicon as an interjection (Roger!), noun (He gave me the roger), or verb (I Roger what you’re asking) to communicate assent or understanding.

Radio code now widely uses the NATO phonetic alphabet, where Romeo represents R. Contrary to folk etymology, Roger is not a backronym for Received Order Given, Expect Results.

Source: dictionary.com