scut (n.2) Look up scut at Dictionary.com
term of contempt for a person, 1873, of unknown origin.
scut (n.1) Look up scut at Dictionary.com
"short, erect tail" (of a rabbit, hare, deer, etc.), 1520s; earlier "a hare" (mid-15c.), perhaps from Old Norse skjota "to shoot (with a weapon), launch, push, shove quickly" (compare Norwegian skudda "to shove, push"), from PIE *skeud- "to shoot, chase, throw" (see shoot (v.)).