Dyad is a noun that refers to something consisting of two parts.
The Greek word duo (DOO oh) means two. By the late 17th century, our word of the day found its way into English and came to refer to anything divided into two parts. Example:
Chris and I made an impressive dyad as a folk band. With him on banjo and me on guitar and vocals were a two-part musical force to be reckoned with.
