This is the 12677th most frequent Spanish word.
negro
Black.
Here, 'negro' is used as an adjective to describe the color of the cat.
El gato negro cruzó la calle.
The black cat crossed the street.
In this case, 'negro' specifies the color of an article of clothing.
Le regalaron un traje negro para la fiesta.
They gave him a black suit as a gift for the party.
'Negro' is used to describe a dramatic change in the color of the sky due to weather change.