[syn: foolhardy, heady, rash, reckless]
The Collaborative International Dictionary of English v.0.48:
Heady \Head"y\ (h[e^]d"[y^]), a. [From Head.]
   1. Willful; rash; precipitate; hurried on by will or passion;
      ungovernable.
      [1913 Webster]
            All the talent required is to be hot, to be heady,
            -- to be violent on one side or the other. --Sir W.
                                                  Temple.
      [1913 Webster]
   2. Apt to affect the head; intoxicating; strong.
      [1913 Webster]
            The liquor is too heady.              --Dryden.
      [1913 Webster]
   3. Violent; impetuous. "A heady currance." --Shak.
      [1913 Webster]
WordNet (r) 3.0 (2006):
heady
    adj 1: marked by the exercise of good judgment or common sense
           in practical matters; "judicious use of one's money"; "a
           wise decision" [syn: judicious, wise, heady]
    2: extremely exciting as if by alcohol or a narcotic [syn:
       heady, intoxicating]
    3: marked by defiant disregard for danger or consequences;
       "foolhardy enough to try to seize the gun from the hijacker";
       "became the fiercest and most reckless of
       partisans"-Macaulay; "a reckless driver"; "a rash attempt to
       climb Mount Everest" [syn: foolhardy, heady, rash,
       reckless]
Moby Thesaurus II by Grady Ward, 1.0:
91 Moby Thesaurus words for "heady":
   agitating, astute, barmy, breathtaking, cagey, charged,
   cliff-hanging, disobedient, disquieting, distracting, disturbing,
   electric, exciting, exhilarating, foam-flecked, foamy, frothy,
   galvanic, headstrong, heart-expanding, heart-stirring,
   heart-swelling, heart-thrilling, impressive, inebriant,
   inebriating, inebriative, inflammatory, insubordinate,
   intoxicating, intoxicative, irresponsible, jarring, jolting,
   lathery, lawless, licentious, maddening, mind-blowing, moving,
   mutinous, overcoming, overmastering, overpowering, overwhelming,
   perspicacious, perturbing, piquant, provocative, provoking,
   rampant, ravishing, reinless, sagacious, savvy, self-willed,
   soapsuddy, soapsudsy, soapy, soul-stirring, spirit-stirring,
   spumose, spumous, spumy, stimulating, stimulative, stirring,
   striking, suddy, sudsy, suspenseful, suspensive, tantalizing,
   telling, thrilling, thrilly, troubling, unaccountable, unbridled,
   unchecked, uncontrolled, uncurbed, undisciplined, ungoverned,
   unreined, unrestrained, unsettling, upsetting, wildcat, willful,
   yeasty