Officially at least, America still calls this Southeast Asian nation Burma, the favored appellation of dissidents and pro-democracy activists who opposed the former military junta's move to summarily change its name 23 years ago.
President Barack Obama used that name during his historic visit Monday, but he also called Burma what its government and many other people have been calling it for years: Myanmar.
Obama's use of that single word was warmly welcomed by top government officials here, who immediately imbued it with significance.
Myanmar presidential adviser Ko Ko Hlaing called the wording "very positive" and said it was an "acknowledgement of Myanmar's government," which has taken major steps toward easing repression and transitioning to democratic rule since the military stepped aside last year.
Speaking aboard Air Force One after Obama's departure, U.S. Deputy National Security Adviser Ben Rhodes said the presidential phrasing was "a diplomatic courtesy" for Myanmar's reformist President Thein Sein.
"It doesn't change the fact that the United States government position is still Burma," he said. "But we've said we recognize that different people call this country by different names. Our view is that is something we can continue to discuss."
The issue is so sensitive that Obama's aides had said earlier Monday he would likely avoid mentioning either politically charged name. But he used both during his six-hour trip — "Myanmar" during morning talks with Thein Sein, "Burma" afterward while visiting with opposition leader Aung San Suu Kyi.
Suu Kyi herself was criticized by the government for calling the nation Burma during a trip to Europe over the summer. The government said she should use the proper name, "Republic of the Union of Myanmar," as stated in the constitution. But Suu Kyi has said "it's for each individual to make his or her own choice as to which he or she uses."
The debate is almost exclusively confined to the English language.
Myanmar, comprising a vast array of ethnic groups, did not exist as a single entity until it was colonized by the British in the 19th century. The country achieved independence in 1948 and took the English-language name used by its former rulers, Burma.
But it was formally known in Burmese, the national language, as "myanma naing ngan" or more colloquially as "bama pyi" or "country of Burma." Both those usages persist, and the national anthem still refers to "bama pyi."
When the now-defunct army junta altered the name in 1989, the change applied only to the English-language title.
But exiles and critics, just like the U.S., kept on using "Burma." And some, including the U.S., still call its main city "Rangoon" instead of Yangon.
But like Myanmar itself, that has all begun to change.
Visiting U.S. senators have used both names. Even at congressional hearings in Washington, there's an occasional mention of "Myanmar."
Associated Press writer Julie Pace contributed to this report from Air Force One. Pitman reported from Bangkok.