also: じょうあん
noun
Shōan era; Jōan era
Japanese era name (年号) spanning 1171–1175 CE. Both readings exist, but しょうあん is standard in modern historical contexts.
承安年間に平清盛が権勢を振るった。
During the Shōan era, Taira no Kiyomori wielded great power.
この文書は承安元年のものと推定される。
This document is presumed to date from the first year of the Shōan era.
The era name 承安 is composed of 承 (receive, succeed) and 安 (peace, stability). The exact derivation is uncertain; it follows typical era-naming conventions of the Heian period.