nonet

Italian nonetto, from nono (“ninth”).

nonet (plural nonets)

1. (music) A composition for nine instruments or nine voices.
   • 1955 January 15, 'The Saturday Review', Recordings Reports: Jazz On LPs, page 38:

     The small-group sides are the best, with the nonet in particular coming through as a sparkling unit that deserves an LP to itself.

2. (physics) A group of nine nuclear or subatomic particles.
3. (computing) A byte of nine bits.
   • 2005, Mark R. Crispin, RFC 4042: UTF-9 and UTF-18

     The 9-bit nonet is a much more sensible representation.

• Tenno, tenno, tenon, tonne