This is the 2293rd most frequent Dutch word.
rap
Quick.
Here, 'rap' is used as an adjective, meaning 'quick' or 'fast', to describe someone's ability.
Hij is erg rap in het oplossen van puzzels.
He is very quick at solving puzzles.
In this context, 'rap' refers to a type of musical style where rhythms and spoken words are combined.
De rap die ze schreven was indrukwekkend.
The rap they wrote was impressive.
In this instance, 'rap' modifies 'talk', acting as an adverb meaning 'quickly' or 'rapidly'.