Where does “heptadiagonal” come from?

heptadiagonal (English) comes from English diagonal, from Middle French diagonal, from Latin diagōnālis, from Ancient Greek διαγώνιος, from Ancient Greek δῐᾰ-, from Ancient Greek διά, from Proto-Indo-European dwís, from Proto-Indo-European dwóh₁ — two.

heptadiagonal (English): Having nonzero entries along the main diagonal,...

Definitions

  1. Having nonzero entries along the main diagonal,...

Ancestry of “heptadiagonal”, step by step

heptadiagonal traces back through two separate lines of ancestry.

via English diagonal

StepLanguageWordMeaning
1EnglishdiagonalJoining two nonadjacent vertices; Having slanted...
2Middle Frenchdiagonal
3Latindiagōnālisdiagonal
4Ancient Greekδιαγώνιοςfrom angle to angle
5Ancient Greekδῐᾰ-apart; through, across; through; in different...
6Ancient Greekδιάthroughout
7Proto-Indo-Europeandwístwice, doubly; in two
8Proto-Indo-Europeandwóh₁two

via English hepta

StepLanguageWordMeaning
1Englishheptaseven
Every word from Proto-Indo-European dwóh₁
heptadiagonal — Etymology, Origin & Word History | Etymology Explorer