Ringtail /(?)/

Ring·tail

Ringtail

n.
  1. A bird having a distinct band of color across the tail, as the hen harrier. (Zool.)
  2. A light sail set abaft and beyong the leech of a boom-and-gaff sail; -- called also ringsail. (Naut.)

Phrases & Compounds
Ringtail boom
a spar which is rigged on a boom for setting a ringtail.