This is the 2362nd most frequent Portuguese word.
sim
"Sim" means "yes" in English.
The word 'sim' is used to affirm or express agreement in this declarative sentence.
Sim, eu concordo com você.
Yes, I agree with you.
Here, 'sim' is used in a reply to indicate acceptance or affirmation of a previously posed question.
Ela perguntou se eu queria um café, e eu respondi 'sim'.
She asked if I wanted a coffee, and I answered 'yes'.
In this case, 'sim' is employed to emphasize the action or fact being stated, which contrasts positively against preceding discourse.