Janjanbi (じゃんじゃん火 or ジャンジャン火) is a atmospheric ghost light told about the legends of various places in the Nara Prefecture. They are considered a type of onibi. In the Miyazaki Prefecture they are also called musabi (むさ火) and in the Kōchi Prefecture, they are also called kechibi.
Their name comes from the "janjan" sound that they make. Also in Nara, there are different legends depending on the area, and different alternate names depending on the area.