Where does “-an” come from?

-an (Old Dutch) comes from Proto-Germanic -aną, from Proto-Indo-European -onom, from Proto-Indo-European -nós — Creates verbal adjectives from roots.

Ancestry of “-an”, step by step

StepLanguageWordMeaning
1Proto-Germanic-anąThe infinitive suffix of strong verbs
2Proto-Indo-European-onom—
3Proto-Indo-European-nósCreates verbal adjectives from roots
Every word from Proto-Indo-European -nós →Every word from Proto-Germanic -aną →Every word from Proto-Indo-European -onom →