consisting of nine.
of, relating to, or noting a numerical system based on the number 9.

noun, plural no·na·ries.

a number in a nonary system.

Origin of nonary

1660–70; < Latin nōnārius of, belonging to the ninth (hour), equivalent to nōn(us) ninth + -ārius -ary Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019