Can someone please explain what a term "Ugly American" really means. I heard it mostly used when people talked about American tourists, but maybe it means something different. Why exactly "ugly"?
Ugly American
'ugly' here bears back to how the Americans behave and carry themselves; not necessarily to how they look physically. A person can be said to be acting "ugly" when they are being rude and mean-spirited, or both.
There was actually a book called "The Ugly American", written in 1958, which was a thinly disguised analysis of what the US was doing wrong in Vietnam. The title actually referred to the less-than-handsome physical appearance of one of the characters in it, but as the rest of the story dealt with issues of poor diplomacy and heavy-handed ideology on the part of American foreign policy agents, it came to have a double meaning -- one literal and one metaphorical. The title of the book has now passed into popular vernacular as the latter.