Definitions for "Nonet"
A composition for nine instruments, rarely for nine voices.
In opera, a musical number for nine solo singers, There is a fine example in act one scene two of  Verdi's Falstaff.
a unit of quantity equal to 9, used mostly in music to describe an ensemble of 9 instruments.
Keywords:  mini, grid, sub, square, region
A mini-grid, sub-grid or region of 9 cells, which is usually a 3x3 square.