Seigaiha is an iconic Japanese pattern, consisting of stylized waves.
Its ancient origins date back to the Persian Sasanian Empire.
It was reportedly used on dance costumes in the Qinghai province of China, and from there probably arrived in Japan.
In the Heian period, Seigaiha became closely associated with Buddhist practices. Some speculate its name derived from Gagaku dance costumes, or from Seigai Kanshichi, a seminal lacquerware artist from the Genroku period, who famously used the motif on most of his works.
The pattern consists of alternating lines of concentric arches that resemble fish scales.
The motif is also a symbol for good luck, often found on formal kimonos such as the Furisode and Kakeshita, tied to the idiomatic expression Shikai nami shizuka 四海波静か, “the waves are calm in four seas”, which in an island nation such as Japan, stands as an auspice for a period of peace.