The Latinate equivalent of the Greek derivative heptadecimal is septendecimal.
It was used by Ellis (Ellis, 1885) to describe a partial 17-limit harmonic system which included the Diminished 7th Chord tuned as 10:12:14:17 and the Dominant 9th chord as 8:10:12:14:17.
Its general meaning is pertaining to [the prime-number] 17 or 17-limit.
Ellis, Alexander J. 1885
English translation of Helmholtz, On the Sensations of Tone...
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