This is the 8390th most frequent Portuguese word.
vallejo
"Vallejo" is not a standard Portuguese word; it may be a proper noun or name.
This usage of 'Vallejo' refers to it as a proper noun, likely the name of a person, specifically a poet.
Eu conheci um poeta chamado Vallejo.
I met a poet named Vallejo.
Here, 'Vallejo' is used as a proper noun referring to the name of a geographical location, namely a city in California.
Vallejo é uma cidade na Califórnia que eu gostaria de visitar.
Vallejo is a city in California that I would like to visit.
In this sentence, 'Vallejo' denotes an author's name, being connected to the possession of the books and their qualities.