The Singapore dollar rose as the central bank was suspected by traders of supporting the currency.
The won kept underperforming as it is seen more sensitive to the yen's weakness, given the competition between South Korea and Japan in exports markets.
Investors built up the largest short positions in the won since the 2008 global financial crisis in the last two weeks, a Reuters poll showed.
Taiwan's dollar ended local trade down 0.5 percent at 31.015 per US dollar, its weakest since October 2010.
The Indonesian rupiah fell as investors took profits from its gains after the central bank raised interest rates and the government increased fuel price earlier this week.
The yen hit a seven-year low against the dollar and a six-year trough versus the euro as speculators rushed to carry trades funded by super-cheap liquidity from the Bank of Japan.