What is the meaning of Rosella?

A parrot belonging to any of the five to eight species in the genus Platycercus (originally specifically Platycercus eximius) which is native to Australia and nearby islands.

Alternative form of roselle (Hibiscus sabdariffa)

poppy (plant of the genus Papaver)

rosella (parrot of the genus Platycercus)

Source: wiktionary.org