Where does “sustenen” come from?

sustenen (Middle English) comes from Old French sustenir, from Vulgar Latin sustenire, from Latin sustineo, from Latin sub-, from Proto-Indo-European upó, from Proto-Indo-European h₃ewp-.

Ancestry of “sustenen”, step by step

StepLanguageWordMeaning
1Old Frenchsustenirto hold up; to support; to support; to sustain
2Vulgar Latinsustenire—
3LatinsustineoI hold up or upright, uphold, keep up, bear up,...
4Latinsub-under, sub
5Proto-Indo-Europeanupóunder, below
6Proto-Indo-Europeanh₃ewp-—
Every word from Proto-Indo-European h₃ewp- →Every word from Proto-Indo-European upó →Every word from Latin sub- →