What was the 1989 Japanese financial bubble commonly called?

The 1989 Japanese financial bubble was commonly called the Japanese asset price bubble.

The bubble involved extraordinary increases in Japanese land and stock prices during the late 1980s. Easy credit, optimistic expectations, financial liberalization, and strong corporate investment helped push asset valuations far above levels supported by rents, earnings, or other fundamentals. Tokyo land prices became especially famous for their enormous reported values.

The Bank of Japan tightened monetary policy in 1989 and 1990. Stock prices then fell sharply, followed by a prolonged decline in land values and a deterioration in bank balance sheets. The Nikkei 225’s peak came at the end of 1989, and the subsequent weakness contributed to what became known as Japan’s Lost Decades.

The terms are related but not interchangeable. The asset-price bubble describes the speculative boom and its collapse; the Lost Decades describe the long period of economic stagnation that followed. Japan’s experience is frequently cited in discussions of credit bubbles, deflation, and the difficulty of repairing banking systems after property booms unwind.