The Collaborative International Dictionary of English v.0.48:

MDMA \MDMA\ n.
   Methylenedioxymethamphetamine, a drug designed to have the
   effects of amphetamines but originally synthesized to avoid
   the drug laws; it is now a controlled substance. It is
   informally called ecstasy. It is used by some abusively and
   illegally without a prescription. [acronym]

   Syn: methylenedioxymethamphetamine, Adam, ecstasy.
        [WordNet 1.5 +PJC]

The Collaborative International Dictionary of English v.0.48:

Ecstasy \Ec"sta*sy\, v. t.
   To fill ecstasy, or with rapture or enthusiasm. [Obs.]
   [1913 Webster]

         The most ecstasied order of holy . . . spirits. --Jer.
                                                  Taylor.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Ecstasy \Ec"sta*sy\, n.; pl. Ecstasies. [F. extase, L.
   ecstasis, fr. Gr. ?, fr. ? to put out of place, derange; ? =
   'ek out + ? to set, stand. See Ex-, and Stand.] [Also
   written extasy.]
   1. The state of being beside one's self or rapt out of one's
      self; a state in which the mind is elevated above the
      reach of ordinary impressions, as when under the influence
      of overpowering emotion; an extraordinary elevation of the
      spirit, as when the soul, unconscious of sensible objects,
      is supposed to contemplate heavenly mysteries.
      [1913 Webster]

            Like a mad prophet in an ecstasy.     --Dryden.
      [1913 Webster]

            This is the very ecstasy of love.     --Shak.
      [1913 Webster]

   2. Excessive and overmastering joy or enthusiasm; rapture;
      enthusiastic delight.
      [1913 Webster]

            He on the tender grass
            Would sit, and hearken even to ecstasy. --Milton.
      [1913 Webster]

   3. Violent distraction of mind; violent emotion; excessive
      grief of anxiety; insanity; madness. [Obs.]
      [1913 Webster]

            That unmatched form and feature of blown youth
            Blasted with ecstasy.                 --Shak.
      [1913 Webster]

            Our words will but increase his ecstasy. --Marlowe.
      [1913 Webster]

   4. (Med.) A state which consists in total suspension of
      sensibility, of voluntary motion, and largely of mental
      power. The body is erect and inflexible; the pulsation and
      breathing are not affected. --Mayne.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ecstasy
    n 1: a state of being carried away by overwhelming emotion;
         "listening to sweet music in a perfect rapture"- Charles
         Dickens [syn: ecstasy, rapture, transport,
         exaltation, raptus]
    2: a state of elated bliss [syn: ecstasy, rapture]
    3: street names for methylenedioxymethamphetamine [syn: Adam,
       ecstasy, XTC, go, disco biscuit, cristal, X, hug
       drug]

Moby Thesaurus II by Grady Ward, 1.0:

105 Moby Thesaurus words for "ecstasy":
   abandon, affection, affectionateness, afflatus, amativeness,
   amorousness, ardency, ardor, beatification, beatitude, bewitchment,
   blessedness, bliss, blissfulness, cheer, cheerfulness, cloud nine,
   craze, delectation, delight, delirium, demonstrativeness, dharana,
   dhyana, ecstasis, ecstatics, elation, enchantment, enjoyment,
   euphoria, exaltation, excitement, exhilaration, exuberance,
   felicity, fervency, fervidness, fervor, fire, fire and fury,
   frenzy, furor, furore, fury, gaiety, gladness, glee, goatishness,
   gratification, gusto, happiness, heart, heartiness, heat, heaven,
   high spirits, horniness, hypnosis, hysteria, impassionedness,
   inspiration, intoxication, joy, joyance, joyfulness, liveliness,
   lovelornness, lovesickness, madness, orgasm, orgy, overhappiness,
   overjoyfulness, paradise, paroxysm, passion, passionateness,
   pleasure, rage, rapture, ravishment, relish, rhapsody, romanticism,
   samadhi, savor, sentimentality, seventh heaven, sexiness, soul,
   spirit, sunshine, susceptibility, tearing passion, thrill,
   towering rage, trance, transport, unalloyed happiness, vehemence,
   verve, warmth, warmth of feeling, yoga trance, zeal