Where does “nine-tenths” come from?

nine-tenths (English) comes from English nine, from Middle English nyn, from Old English niġon, from Proto-Germanic newun, from Proto-Indo-European h₁néwn̥ — nine.

nine-tenths (English): Nine parts out of ten; 90%; 9/10; Almost all; the...

Definitions

  1. Nine parts out of ten; 90%; 9/10; Almost all; the...

Ancestry of “nine-tenths”, step by step

nine-tenths traces back through two separate lines of ancestry.

via English nine

StepLanguageWordMeaning
1EnglishnineA numerical value equal to 9; the number...
2Middle Englishnynnine
3Old Englishniġonnine
4Proto-Germanicnewunnine
5Proto-Indo-Europeanh₁néwn̥nine

via English tenths

StepLanguageWordMeaning
1Englishtenthsplural of tenth
Every word from Proto-Indo-European h₁néwn̥Every word from Proto-Germanic newunEvery word from Old English niġon