Dick has been short for Richard since about the 13th century and the reason remains obscure because the etymology of the name Richard springs from a corruption of the Latin rex meaning ‘king’ or ‘ruler’ and the Old English hard meaning ‘strong’ or ‘powerful’. Etymologists believe the original shortening of Richard was ‘Ric’ and that ‘Dick’ came about purely because of rhyming, but this seems to be no more than a supposition. What is certain is that Dick has been a general term for a chap, lad or fellow since the late 16th century as in Tom, Dick and Harry. Dick meaning penis is first cited as military slang from about 1860. Dick as slang for a detective as in a ‘private dick’ is originally American and dates from the early 20th century.