This is the 346th most frequent Swedish word.
bäst
Best.
Here 'bäst' is used as a superlative adjective to indicate the highest degree of quality.
Hon är bäst i klassen.
She is the best in the class.
In this sentence, 'bäst' functions as an adverb to recommend the most prudent action.
Det är bäst att vi går nu.
It's best that we leave now.
Here 'bäst' is used as part of the derived noun 'bästis,' describing someone's closest or favourite friend.