ouroboros

1. (mythology) A serpent, dragon or worm that eats its own tail, a representation of the continuous cycle of life and death.Examples: "The alchemists were fond of picturing their opus as a circulatory process, as a circular distillation or as the uroboros, the snake biting its own tail, and they made innumerable pictures of this process."; "Khepera eating his own seed is a model of Romantic creativity, where the self is isolated and sexually dual. Khepera bent over himself is a uroboros, the serpent eating its own tail, a magic circle of regeneration and rebirth. The uroboros is the prehistoric track of natural cycle, from which Judaism and Hellenism make a conceptual break."; "One myth speaks of Ouroboros, a serpent-like creature that survived and regenerated itself by eating only its own tail. By neither taking from nor adding to its environment, this creature was said to be completely environmentally benign and self-sufficient."

2. (by extension) Anything of a circular or recursive nature.Examples: "Like an ouroboros, the story created and informed by the writer’s own experience suddenly flipped back on itself, Childress’s life now reflecting the story rather than the other way around."; "The result is a statistical ouroboros: a self-reinforcing discrimination machine that amplifies social inequalities under the guise of technical neutrality."broadly