This is the 82nd most frequent Norwegian word.
beste
"Beste" means "best" in English.
The word 'beste' is used here in its superlative form to describe the highest quality friend, indicating 'best'.
Han er min beste venn.
He is my best friend.
In this sentence, 'beste' is used as a part of a noun phrase 'det beste', abstractly describing the highest quality aspect or feature of an experience.
Det beste med turen var utsikten.
The best part of the trip was the view.
Here, 'beste' refers to a superlative degree, with the implication of achieving the highest standard or quality, used substantively.