looper

noun6

1. •
   A (usually electronic) tool for creating music loops.
2. •
   A moth having a caterpillar which arches its body into a loop in order to bring the back part of the body forward as it walks due to having fewer prolegs, including inchworms or measuring worms in the family Geometridae and some species in the family Noctuidae.
3. •
   (slang) A golf caddy

   • "There ain't much to tell. I'm the king of the caddies, the greatest fucking looper who ever packed a bag." — 1981
4. •
   Synonym of blooper (“a fly ball that is weakly hit just over the infielders”).

   • With one out and runners on second and third, Cavan Biggio hit a looper up the middle that eluded hustling shortstop Tim Anderson in short centre field. — 2022
5. •
   An instrument or tool, such as a bodkin, for forming a loop in yarn or cord, etc.
6. •
   (slang, offensive) A crazy person; a maniac.