Colonel is perhaps the classic example of this orthographic waywardness. The word comes from the old French coronelle, which the French adapted from the Italian colonello (from which we get colonnade). When the word first came into English in the mid-sixteenth century, it was spelled with an r, but gradually the Italian spelling and pronunciation began to challenge it. For a century or more both spellings and pronunciations were commonly used, until finally with inimitable illogic we settled on the French pronunciation and Italian spelling.
