Where does “systær” come from?
systær (Old Danish) comes from Old Norse systir, from Proto-Norse ᛊᚹᛖᛊᛏᚨᚱ, from Proto-Germanic swestēr, from Proto-Indo-European swésōr, from Proto-Indo-European su-h₁ésh₂-ōr, from Proto-Indo-European h₁ésh₂r̥ — blood.
systær (Old Danish): sister
Ancestry of “systær”, step by step
Words derived from “systær”