This is the 640th most frequent Portuguese word.
cuiabá
Cuiabá: A city in central Brazil, capital of the state of Mato Grosso.
Here, 'Cuiabá' is a proper noun, the name of a city.
Cuiabá é uma cidade localizada no estado do Mato Grosso.
Cuiabá is a city located in the state of Mato Grosso.
In this case, it is derived to form 'cuiabano', indicating someone from Cuiabá.
Eu conheci um amigo que é cuiabano, ou seja, nasceu em Cuiabá.
I met a friend who is 'cuiabano', that is, he was born in Cuiabá.
Here 'Cuiabano' is used as an adjective describing climate related to Cuiabá.