octet

(ŏk-tĕtˈ)

1. Music
   a. A composition for eight voices or eight instruments.
   b. A group of eight singers or eight instrumentalists.
2. A group of eight: “A train of heavy wagons rumbled north on the Winnipeg Trail, drawn by octets of oxen” (Garrison Keillor).
3. See octave.
4. A set of eight valence electrons in an atom or ion, forming a stable configuration.