This is the 2623rd most frequent German word.
bester
"Best" or "finest" (superlative form of "gut," meaning good).
The word 'Beste' is used here substantively, functioning like a noun, as it represents 'the best' in a generic or abstract sense.
Wir haben das Beste aus der Situation gemacht.
We made the best of the situation.
The word 'bester' is used here as a superlative adjective, agreeing in gender, case, and number with the masculine singular noun 'Freund'.
Peter ist mein bester Freund.
Peter is my best friend.
Here, 'beste' is a superlative adjective describing the masculine singular noun 'Kuchen', following the definite article in the nominative case.