A dramatic device in which a future event is inserted into the normal chronological flow of a narrative.(noun)
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Use "flashforward" in a sentence
"If he were under other pressures that we do not understand (not his first time to the island or that the flashforward is really a flashback) then his behavior would be in harmony with that reality."
"I think complaining about questions raised in the flashforward is a little ridiculous."
"In the beginning, I thought it was a "flashforward" rather than a flashback (or, technically, the scenes in the island were the flashbacks), but discarded it when Jack talked about his father in the hospital."