/ ɒmˈnɪsiənt; NAmE ɑːm-/ adjective
( formal ) knowing everything :
The novel has an omniscient narrator.
► om·nis·ci·ence / -siəns; NAmE / noun [ U ]
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WORD ORIGIN
early 17th cent.: from medieval Latin omniscient- all-knowing, based on scire to know.