Can you use and/or in formal writing?
Please do not use “and/or” in either formal or informal writing. In common English, the “or” is a “non-exclusive or” which means “either A or B, or A and B”. When I say “I can have a banana OR I can have coffee” then I am also OK with having both. Having a banana does not prevent me from having coffee.
Does and/or need a slash?
A couple of readers inquired about and/or, for obvious reasons. Grammar books generally disregard the slash, but most of them have a lot to say about and/or. Several authorities recommend replacing and/or with or alone. As Follett points out, “generally or includes and.
Is there a word for and or?
And/or (also and or) is a grammatical conjunction used to indicate that one or more of the cases it connects may occur. It is used as an inclusive or (as in logic and mathematics), while an or in spoken language might be inclusive or exclusive.
What does and/or mean in a contract?
And/or, however, is not ambiguous at all. It has a definite, agreed-upon meaning: when used properly, the construct means “A or B or both.” In most areas of law, there simply is no compelling reason to avoid using and/or. The term is clear and concise.
Does and/or mean both?
In summary, avoid and/or and simply use or, they mean the same thing. Context will suggest the correct interpretation of or without the need to be explicit. And if context is misleading and you must be explicit, say “A or B, or both“. And/or is generally used when either one or both of the options may be true.
What does and mean legally?
According to the legal commentators, when used together with “and,” the word “or” usually includes “and” and the “and/or” phrase means “either or both of.” Inclusion of the “/” would not have corrected any error, ambiguity or confusion already inherent in the use of the “and” “or” conjunctive-disjunctive.

David Nilsen is the former editor of Fourth & Sycamore. He is a member of the National Book Critics Circle. You can find more of his writing on his website at davidnilsenwriter.com and follow him on Twitter as @NilsenDavid.