Where does “-ist” come from?

-ist (Old High German) comes from Proto-Germanic -istaz, from Proto-Indo-European -istHos, from Proto-Indo-European -yōs, from Proto-Indo-European -yoss.

Ancestry of “-ist”, step by step

StepLanguageWordMeaning
1Proto-Germanic-istaz-est
2Proto-Indo-European-istHos—
3Proto-Indo-European-yōsForms adjectives from roots, meaning "very" or...
4Proto-Indo-European-yoss—
Every word from Proto-Indo-European -yoss →Every word from Proto-Germanic -istaz →Every word from Proto-Indo-European -yōs →