Definition of 'Yen ETF'
Exchange-traded funds that invest primarily in yen-backed assets such as short-term debt instruments and bonds, or hold the currency in simple interest-bearing accounts that pay the current money market yields in Japan. Some Yen ETFs will match (with a dividend yield) the current income earned on the yen assets, or may use that income to pay the expenses of managing the ETF.
Investopedia explains 'Yen ETF'
Unlike basic money market funds, Yen ETFs do not seek to maintain share price stability (as in $1 per share); performance is primarily driven by the performance of the Japanese yen compared to the the U.S. dollar.
The Japanese yen is one of the most traded currencies in the world, along with the dollar and the euro. Japan's historically low interest rates make it a sought after currency for borrowing, but the borrowed funds are often used to invest in foreign securities and debt.