A Jew and Jews
While we are at this racial slur thing: I was told that “He is a Jew” sounds offensive, but “He is Jewish” does not, because the former sounds like a Nazi trying to identify Jews from the rest, which is odd because he would not be speaking English in the first place. To make the matter more confusing, I was told that “They are Jews” is not offensive. Singular is offensive but plural isn’t? You would probably say, “He is American” instead of “He is an American”, but either way it does not sound offensive.