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Adverb: instantly  in-stunt-lee
  1. Without delay or hesitation; with no time intervening
    "he answered instantly";
    - immediately, straightaway, straight off, directly, now, right away, at once, forthwith, like a shot [informal], right now, right off the bat [N. Amer, informal], instantaneously, outright, in a flash, tout de suite

See also: then and there