Cur

Cur refers to a dog, usually of mixed ancestry. In common usage, the term is often derogatory; fighting dogs that regress to growling rather than maintain calm are referred to as 'curs'. The derivation of the word "cur" is uncertain. According to the Dictionary of True Etymologies (Room, Adrian, Routledge & Kegan Paul, London and New York, 1986), "cur" is a Germanic word, possiblly from Old Norse meaning to growl. If so, then the word is onomatopoeic, and a cur is a dog that goes "grrr."