This is the 658th most frequent Bulgarian word.
черно
"Черно" means "black" in English.
Черно describes the color of the clothing item, acting as an adjective modifying 'яке'.
Купих черно яке.
I bought a black jacket.
Черно is used to describe the coffee, meaning without milk or other additions, functioning as an adjective.
Той предпочита черно кафе.
He prefers black coffee.
Черно is used metaphorically here to evoke an emotion related to the dark and mysterious nature of the night sky, functioning as a descriptive adjective.