This is the 130th most frequent Portuguese word.
sistema
A set of connected things or parts forming a complex whole.
In this sentence, 'sistema' is being used to refer to an infrastructure or network system, specifically related to roads.
O sistema rodoviário no Brasil é vasto e complexo.
The road system in Brazil is vast and complex.
Here, 'sistema' refers to an organized mechanism or set of devices designed for safety or surveillance.
Precisamos instalar um sistema de segurança na nossa casa.
We need to install a security system in our house.
In this context, 'sistema' is used to describe an organized cosmic structure, specifically the gravitational arrangement of celestial bodies around the Sun.