In programming we have the term "xor gate" for when one of two things is allowed, but not both. That is, P XOR Q is true if and only if exactly one of them is true, false otherwise.

But English is not always so clearcut as programming. Is there an English word that serves the same function? That is, is there a word in English such that people think

X is the case ___ Y is the case

is true when exactly one of X and Y is true but not both? (For contrast, "X is the case and Y is the case" is true only when both X and Y are the case at the same time, and nothing less)

closed as unclear what you're asking by JJ for Transparency and Monica, Lawrence, RegDwigнt Aug 6 '18 at 9:33


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    Have you got an example in mind of how you would use such a word? – John Go-Soco Aug 6 '18 at 8:24
  • An example would clarify whether you want a term to replace xor in something like "this xor that", or whether you want a term to describe the mutual exclusion. Please use the edit link to add an appropriate example to your question. You can use "___" to indicate where the word should go. – Lawrence Aug 6 '18 at 9:06
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    @Lawrence in order to understand the question, one should know the function of XOR. Phrases "Either-Or" and "Mutual Exclusion" is technically wrong. You can't use them for XOR. For me, this question is very clear. OP is asking a English word for XOR (which he thinks is not a word, but a type of Gate (in electronics)) – Ubi hatt Aug 6 '18 at 9:59
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    But the natural way to invoke XOR in English is to say either-or. "Either it will rain or I will play baseball" usually means one of these will happen, not none and not both. – Mitch Aug 6 '18 at 14:05
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    You can also say, You can only have one or the other. The use of only gives the meaning of the conjunction exclusivity. – Jason Bassford Supports Monica Aug 6 '18 at 22:12

Not exactly a single word, but how about:


You could also use:

Not possible at the same time

  • The quote about either-or is somewhat misleading. It's referring to the use of the term as an adjective before a noun - like "this is an either-or situation". If you simply have "either this or that", it doesn't always translate to "this xor that". – Lawrence Aug 6 '18 at 9:02
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    Can you provide a published example of either-or acting as an inclusive or, please? – G Tony Jacobs Aug 6 '18 at 12:20
  • I, too, can't think of a single instance when either . . . or has been used in an inclusive manner. – Jason Bassford Supports Monica Aug 7 '18 at 1:37
