means A small, slender carnivorous mammal of the weasel family, brown in summer with a black-tipped tail, whose white winter coat is prized as ermine.

from The word surfaces in late Middle English as 'stote,' and its deeper roots are honestly murky — etymologists shrug here. It may be related to Old Norse 'stútr' (a bull or stubborn creature) and to dialect words for a gnat or stinging fly, hinting at something small and pestering, but none of this is certain. Quite separately, the animal's winter coat earned its own famous name: 'ermine,' from Old French 'ermine,' possibly meaning 'Armenian (mouse)' — the white fur that ended up trimming the robes of kings.