Back edge
From FLWiki
Also called a loop or cycle.
A back edge is any edge added to a graph that would cause an entity to directly or indirectly become its own predecessor. Back edges are for display only, and do not participate in confidence calculations, nor do they have edge weights. They are useful for denoting virtuous circles and vicious circles.
Although Flying Logic documents support adding back edges, since only regular (non-back) edges are involved in confidence calculations, the actual data model of a Flying Logic document is still that of a directed acyclic graph.
