loop (n.)

late 14c., "a fold or doubling of cloth, rope, leather, cord, etc.," of uncertain origin. OED favors a Celtic origin (compare Gaelic lub "bend," Irish lubiam), which in English was perhaps influenced by or blended with Old Norse hlaup "a leap, run" (see leap (v.)). As a feature of a fingerprint, 1880. In reference to magnetic recording tape or film, first recorded 1931. Computer programming sense "sequence of instructions executed repeatedly" first attested 1947.

c. 1400, loupen, "to draw (a leash through a ring)," from loop (n.). Sense of "form into a loop or loops" (transitive) is from 1832; transitive meaning "form (something) into loops" is from 1856. Related: Looped (1934 in the slang sense "drunk"); looping. Loop the loop (1900) originally was in reference to roller-coasters at amusement parks.

"Loop-the-Loop" is the name of a new entertainment which goes further in the way of tempting Providence than anything yet invented. The "Loop" is an immense circle of track in the air. A car on a mimic railway shoots down a very steep incline, and is impelled around the inner side of this loop. ... The authorities at Coney Island are said to have prohibited "looping-the-loop" because women break their corset strings in their efforts to catch their breath as they sweep down the incline, and moreover, a young man is reported to have ruptured a blood vessel in his liver. ["Philadelphia Medical Journal," Aug. 10, 1901]