Synonyms and related words :
at once, directly, forthwith, immediately, in a flash, in a jiff, in a jiffy, in a twink, in a twinkling, in no time, in nothing flat, in short order, instanter, instantly, just now, just then, momentaneously, momentarily, momently, on the dot, on the instant, on the nail, on the spot, promptly, pronto, right now, tout de suite, without delay