stack exchange 上的两个答案
>It isn't always actually used with full precision, though, so, as usual, context has to be taken into account. If somebody says, "select either A or B", for example, they definitely mean that you should not select both. If they say "if either A or B is true", though, they probably mean a non-exclusive OR, and the condition is still true if both A and B are true.
>Usually, the inclusive sense is used in mathematics and the exclusive sense in everyday life. In any case, further specification or context will remove any doubt.
所以如果是 choose either A or B 这样那肯定就是 xor 了，但其他情况看语境也可能与 or 同义
还有
math.toronto.edu 给了同样的解释：
>In every day language we use the phrase "either A or B" to mean that one of the two options holds, but not both.For example, when most people say something like ``You can have either a hot dog or hamburger," they usually aren't offering you both. The use of ``either/or" in everyday English is usually divisive, and meant to imply there are only two options: A or B, but not both A and B. (The use of "or" in this way is sometimes referred to as "exclusive or.")
>However, the use of "either A or B" in mathematics allows the option that both A and B hold. (The use of "or" in this way is sometimes referred to as "inclusive or.") For example, in mathematics, the statement "If x is a real number, then either x≤0 or x≥0" allows the possibility that x satisfies both x≤0, as well as x≥0 (which is true of the real number 0).