Where does “Fluffy” come from?

Fluffy is an English adjective formed from fluff with the suffix -y, tracing back through Middle French -ie and Latin -ia and -ivus to Proto-Indo-European -kos.

Ancestry of “Fluffy”, step by step

Step	Language	Word	Meaning
1	English	fluff	Anything light, soft or fuzzy, especially fur,...
2	English	floow	woolly substance, down, nap, lint

Every word from English floow →

Fluffy — Etymology, Origin & Word History | Etymology Explorer