Where does “heptadecad” come from?

heptadecad (English) comes from English decad, from English decade, from Middle English decade, from Middle French decade, from Latin decās, from Ancient Greek δεκάς, from Ancient Greek -ᾰ́ς, from Proto-Indo-European -ónts — sound, voice.

heptadecad (English): A group of seven decads arranged to produce twenty-four tones

Definitions

  1. A group of seven decads arranged to produce twenty-four tones

Ancestry of “heptadecad”, step by step

heptadecad traces back through two separate lines of ancestry.

via English decad

StepLanguageWordMeaning
1EnglishdecadArchaic form of decade
2EnglishdecadeA group, set, or series of ten, particularly
3Middle Englishdecade
4Middle Frenchdecadea series of 10 books
5Latindecāsa decade (period of ten years)
6Ancient Greekδεκάςthe number ten; a group of ten, decade
7Ancient Greek-ᾰ́ςgroup of
8Proto-Indo-European-óntsDerives nouns denoting body parts
9Hungarianöntto pour; to cast; accusative singular of ön
10Hungarianönyou
11Hungarianön-self-
12Turkishönfront
13Ottoman Turkishاوكvoice (of human or animal); sound
14Proto-Turkicǖnsound, voice

via English hepta

StepLanguageWordMeaning
1Englishheptaseven
Every word from Proto-Turkic ǖn