[1] : WordNet (r) 2.0

straightaway
     adj : performed with little or no delay; "an immediate reply to my
           letter"; "prompt obedience"; "was quick to respond"; "a
           straightaway denial" syn: immediate, prompt, quick
     n : a straight segment of a roadway or racecourse syn: straight
     adv : without delay or hesitation; with no time intervening; "he
           answered immediately"; "found an answer straightaway";
           "an official accused of dishonesty should be suspended
           forthwith"; "come here now" syn: immediately, instantly,
            straight off, directly, now, right away, at
           once, forthwith, in real time, like a shot
see also:
immediate prompt quick straight immediately instantly 
straight off directly now right away at once 
forthwith in real time like a shot 

[2] : Moby Thesaurus II by Grady Ward, 1.0

85 moby thesaurus words for "straightaway":
   pdq, air line, all at once, all together, apace, at a blow,
   at a stroke, at once, at one blow, at one jump, at one stroke,
   at one swoop, at one time, away, axis, beeline, chord, decisively,
   diagonal, diameter, direct, direct line, directly, directrix, edge,
   expeditiously, first, forthwith, great-circle course, immediate,
   immediately, in a hurry, in no time, instanter, instantly,
   irreversible, normal, now, on the instant, on the spot, one-way,
   per saltum, perpendicular, pretty damned quick, promptly, pronto,
   quickly, radius, radius vector, right away, right line, right now,
   right off, secant, segment, shortcut, side, simultaneously,
   smartly, speedily, straight, straight course, straight line,
   straight stretch, straightforward, straightway, streamline, subito,
   summarily, swiftly, tangent, then and there, this minute,
   this very minute, transversal, unbroken, undeviating,
   unidirectional, uninterrupted, uno saltu, unswerving, vector,
   with all speed, without delay, without further delay

Straightaway >> S Words
Straightaway, definition of term: Straightaway
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