This is the 5425th most frequent French word.
bella
"Bella" is not a French word; it is Italian and means "beautiful" (feminine).
The word 'Bella' here functions as a proper noun, specifically a name for a cat.
La féline s'appelle Bella.
The feline is named Bella.
The word 'bella' here is used informally as an adjective meaning 'beautiful', borrowed from Italian.
Cela semble être une vie très bella.
That seems like a very beautiful life.
'Bella' is used here as a noun, referring to the concept of the name itself.