Where does “tridiagonal” come from?

tridiagonal (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.

tridiagonal (English): Having nonzero elements only in the main diagonal...

Definitions

  1. Having nonzero elements only in the main diagonal...

Ancestry of “tridiagonal”, step by step

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

Words derived from “tridiagonal

Every word from Proto-Indo-European dwóh₁
tridiagonal — Etymology, Origin & Word History | Etymology Explorer