Bluastri means "bluish" and is a less common, more descriptive way to talk about the color blue. It adds a nuanced touch, suggesting a shade of blue rather than a pure, vibrant blue.
In the song, Alfa sings, "I tuoi occhi bluastri son come astri in un cielo blu" (Your bluish eyes are like stars in a blue sky). This word choice makes the imagery more poetic and specific, highlighting the unique color of the person's eyes and making them stand out.
Alfa's