Where does “under-” come from?

under- (Middle English) comes from Old English under-, from Proto-Germanic under, from Proto-Indo-European h₁entér, from Proto-Indo-European h₁en — in; in, inside.

Ancestry of “under-”, step by step

StepLanguageWordMeaning
1Old Englishunder-between, among; beneath; subordinate to
2Proto-Germanicunderamong, between; under, beneath; under
3Proto-Indo-Europeanh₁entérbetween
4Proto-Indo-Europeanh₁enin; in, inside

Words derived from “under-”

Every word from Proto-Indo-European h₁en →Every word from Proto-Indo-European h₁entér →Every word from Proto-Germanic under →