stoat

Etymology

Comes from Middle English stote ("the ermine, especially in its brown summer coat"), of uncertain origin. It bears some resemblance to Old Norse stutr ("bull"), Swedish stut ("bull, steer") and Danish stud ("steer") (see also English stot), though the semantic link is difficult to make unless a common origin lies in "(brown?) male mammal". It is first attested in the mid 1400s.