Take the 2-minute tour ×
English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. It's 100% free, no registration required.

Possible Duplicate:
Alternatives to “and/or”?

Is it okay to say "and/or"? How else might I phrase a sentence like the following?

The amount of happiness displayed by the bunny increased when either the bunny was well fed and/or when the bunny was watching a sunset.

I am writing a scientific paper, and it is important that the events have the same effect when they occur separately or together; I have written a trivial example replacing esoteric words with more familiar ones.

share|improve this question
add comment

marked as duplicate by Kosmonaut Feb 17 '11 at 1:44

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

5 Answers

Shouldn't the title say "...and/or how else might I achieve this?" ;-)

In the sentence as presented, the use of the initial "either" really requires that you follow it up only with an "or"; "either/and" just doesn't work. If the options given are not inherently exclusive, they should be understood to be "one, the other, or both".

Alternatively, you could say "the amount of X increased when Y, and also when Z."

Or, "the amount of X increased when Y, or when Z (increasing linearly/exponentially/whatever when both Y and Z)."

share|improve this answer
thanks for the tip. I must have been over thinking this; I changed the title according to your excellent suggestion. –  1'' Feb 14 '11 at 23:35
add comment

If it's used repeatedly in your paper and it's important to specify, then I'd probably stick to "and/or" if the intention is clear: it's fairly widely used and, compared to adding a parenthesis such as "(or where both cases hold)", it has the merit of being concise.

I also wouldn't get too bogged down: if the editor really doesn't like it for some reason, they'll change it or ask you to change it. For what it's worth, I translate professionally (both academic material and more general texts) and have never been asked to avoid "and/or".

[Conversely, for my own sanity, I have stopped using "iff" for "if and only if" after this 'misspelling' was highlighted to me various times.]

share|improve this answer
But what's wrong with iff? :) –  Marthaª Feb 15 '11 at 1:29
add comment

I believe a scientific paper is expected to use fairly literate English, so use of short-cuts such as "and/or" might be inappropriate.

However your peer reviewers are likely to be preoccupied with the appropriateness of "bunnies" enjoying sunsets, so it won't detract greatly from the result.

If "it is important [to record] that the events have the same effect when they occur separately or together" - why not just say so?

share|improve this answer
add comment

As you have used either in the first part of your sentence, the second part of the sentence must only use or, as either-or is a complementary pair, one must follow the other. Either-and would not make the correct grammatical sense.
In the above case, the use use of either-or and and would make two drastically different sentences.

share|improve this answer
add comment

I've heard the term "XOR" used in casual conversation, but only among math/computer nerds like myself. If more people accepted the term it would make things a lot easier.

share|improve this answer
"A xor B" does not mean "A and/or B". It means "A or B, but not both" (i.e., "exactly one of A and B"). If you're going to use a technical word and use it incorrectly, you'll just confuse nearly everyone. –  ShreevatsaR Feb 15 '11 at 6:08
@ShreevatsaR However, if "xor" was used then "or" could be used in its boolean sense meaning "and/or" without any ambiguity. But I can't really see that taking off in non-geek English. –  neil Feb 15 '11 at 12:38
@neil that might be acceptable on a technical paper if the terms are defined that way –  jk. Feb 15 '11 at 18:16
@neil. Thanks, that's what I meant. I just realized how unclear my answer was. –  Yitzchak Feb 21 '11 at 18:02
add comment

Not the answer you're looking for? Browse other questions tagged or ask your own question.