single-tail

In BDSM a "single-tail" is a single-lashed whip like a bull whip or a signal whip that is used by dog-sled riders. Floggers, cats, querts and other whips have 2 or more lashes. Paddles, canes, switches etc. are rigid and are less often referred to as "whips." Single-tails are particularly fierce whips.

I went to this crazy hot party last night. I saw this Dom, he didn't just spank his slave, he used a single-tail on her. Her back was a spider-web of welts. He was an artist. It was so fucking hot.