The fact of a thing occurring simultaneously with something else; correlation.(noun)
An instance of a thing occurring simultaneously with something else; co-incidence.(noun)
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Use "co-occurrence" in a sentence
"But one can imagine some kind of statistical technique that will be able to detect the simultaneous co-occurrence of c-fos generation in particular groups of neurons."
"The co-occurrence of the events cannot be explained as one event causing another event—Jung called the connection acausal."
"Again, synchronicities are the highly improbable occurrence of two or more events in close proximity, where one is not causing the other but suggests the existence of some invisible influences or energies causing their co-occurrence."