Gopher is the forex slang term for the USD/JPY currency pair, where USD is the base currency and JPY is the quote currency.
Gopher shows how many Japanese yen buy one US dollar. At USD/JPY = 150.00, one US dollar equals 150 Japanese yen.
Gopher is one of the most liquid pairs and reacts sharply to Federal Reserve rate decisions, Bank of Japan policy, US Treasury yields, and safe-haven demand for the yen during global risk-off moves.
You see USD/JPY = 150.00, so one US dollar equals 150 Japanese yen.
If USD/JPY rises to 151.00, traders say Gopher has risen as the US dollar gains on the yen. If it falls to 149.00, traders say Gopher has fallen.