Shinengo (literally means private nengo; nengo is a name of an era) was the name of an era which was not declared by a dynasty that had a stable administrating power in South East Asia, where the name of an era was used as the method of counting years.
私年号（しねんごう）は、紀年法として元号を用いた東アジアにおいて、安定した統治能力を確立した王朝が定めた元号以外の年号をさす。