nonadic

From nonad + -ic.

nonadic (not comparable)

1. Of or pertaining to a nonad; ninefold.
   • 2020, John Krey, The Structure of Knowledge Using Natural Patterns, page 11:

     The five fingers on each hand are punctuated continua like the nonadic nine planets.

• This word has been coined on the model of tetradic, octadic etc, but has little usage; the usual term is enneadic.

• nonacid