The definition of either or is an expression used to indicate that there are only two options or that both of two options are acceptable or equivalent.
(adjective)An example of either or is when you are offered either spaghetti or cereal for dinner and are different between the two so you say "either or" to indicate that both would work.
See either-or in Webster's New World College Dictionary
adjective
See either-or in American Heritage Dictionary 4
noun
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