The dollar index, which tracks the U.S. currency against a basket of six major counterparts, fell another 0.40 percent to 101.37. It had risen to a one-week high on Wednesday.
The euro gained 0.4 percent to $1.0622 after skidding to a 14-year low of $1.0340 last week.
"There's 'Good Trump' and 'Bad Trump' for the markets. Will 'Good Trump' return before the inauguration?" said Ayako Sera, market strategist at Sumitomo Mitsui Trust Bank in Tokyo.
While some investors who missed out on the dollar's post-election rally were still looking to buy on dips, others were seeking to pare their long dollar positions in case the coming reality of Trump's administration fail to live up to expectations, market participants said.
But there has also been a broadly stronger tone to commodities-linked currencies like the Canadian and New Zealand dollars. The former hit its highest since October in early trade in Europe and the kiwi gained more than 1 percent.