The definition of simultaneous is things that are going on at the same time.(adjective)
When two television shows are on different channels at the same time, this is an example of a situation where the shows are simultaneous.
See simultaneous in Webster's New World College Dictionary
Origin: ML simultaneus < simultas, simultaneity < L, competition, rivalry < simul: see same
See simultaneous in American Heritage Dictionary 4
Origin: Latin simul, at the same time; see sem-1 in Indo-European roots
Origin: + English -taneous (as in instantaneous).
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