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English definition of “or”

or

conjunction (EXPLAIN)   /ɔr, ər/
used to show that a word or phrase means the same as, or explains or corrects, another word or phrase: Photons, or individual particles of light, travel huge distances in space. Things were going well, or seemed to be, but the relationship had already begun to change.
(Definition of or conjunction (EXPLAIN) from the Cambridge Academic Content Dictionary © Cambridge University Press)
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