I would guess it’s wordplay on other models being named after animals (llama, vicuña) and figurative use of “ferret”. https://en.m.wiktionary.org/wiki/ferret h

I would guess it’s wordplay on other models being named after animals (llama, vicuña) and figurative use of “ferret”. https://en.m.wiktionary.org/wiki/ferret https://en.m.wiktionary.org/wiki/ferret: “3. (figurative) A diligent searcher”