This is the 826th most frequent Norwegian word.
søster
"Søster" means "sister" in English.
The word 'søster' here is used as a noun denoting a family member, specifically a sibling who is female.
Jeg besøkte min søster i helgen.
I visited my sister during the weekend.
Here, 'søster' is used metaphorically to describe a close relationship akin to that of siblings.
Hun har vært som en søster for meg.
She has been like a sister to me.
In this plural form 'søstre', the word refers to female siblings collectively.