This is the 976th most frequent Catalan word.
rosa
"Rosa" in Catalan means "rose" (the flower) or "pink" (the color).
Here, 'rosa' is used as a noun meaning a flower (a rose in this case).
El jardí està ple de roses belles.
The garden is full of beautiful roses.
Here, 'rosa' is used as an adjective describing the color pink.
El cel es torna rosa al capvespre.
The sky turns pink in the evening.
Here, 'rosa' again refers to the rose flower, but now it is singular and pertains to a specific rose.