This is the 8206th most frequent Portuguese word.
trê
"Trê" is not a standard Portuguese word and may be a typo or variation.
Here, 'três' is used as a numeral to denote the quantity of birds.
Eu vi três pássaros voando no céu.
I saw three birds flying in the sky.
In this sentence, 'três' expresses a specific duration of time in hours.
Três horas se passaram desde o início do filme.
Three hours have passed since the beginning of the film.
In this context, 'três' refers to the sequence year of the project, indicating its chronological position.