"The original English name for this bird, dating back to at least 1465, is the ree, derived from a dialectical term meaning "frenzied" (Lockwood 1984). A later name reeve, which is still used for the female, is of unknown origin, but may be derived from the shire-reeve, a feudal officer, likening the male's flamboyant plumage to the official's robes. The current name was first recorded in 1634, and is derived from the ruff an exaggerated collar fashionable from the mid-sixteenth century to the mid-seventeenth century, since the male bird's neck ornamental feathers resemble the neck-wear (Cocker & Mabey 2005)." - Wikipedia to the rescue
