Where does “-sum” come from?

-sum (Old Frisian) comes from Proto-Germanic -samaz, from Proto-Germanic samaz, from Proto-Indo-European somHós, from Proto-Indo-European sem- — together, one.

Ancestry of “-sum”, step by step

StepLanguageWordMeaning
1Proto-Germanic-samazsame as
2Proto-Germanicsamazsame, alike
3Proto-Indo-EuropeansomHóssame, alike
4Proto-Indo-Europeansem-together, one

Words derived from “-sum”

Every word from Proto-Indo-European sem- →Every word from Proto-Indo-European somHós →Every word from Proto-Germanic samaz →