Skaarslien - what is in farm name

My great grandmother was born on the farm of Skaarslien (baptism record), Gausdal in 1832. In various records, I have seen what appears to be the same farm as Skaarslien, Skaars-eie, Skaars-eic and Skaars-eict. Would someone be able to tell me what the different forms of this mean or why it changes in spelling when I believe it is all the same place? Thank you, Dusty