Source : Webster's Revised Unabridged Dictionary (1913)

Lascivious \Las*civ"i*ous\, a. [L. lascivia wantonness, fr.
   lascivus wanton; cf. Gr. (?) lecherous, (?) to wish, Skr.
   lash to desire.]
   1. Wanton; lewd; lustful; as, lascivious men; lascivious
      desires. --Milton.

   2. Tending to produce voluptuous or lewd emotions.

            He capers nimbly in a lady's chamber To the
            lascivious pleasing of a lute.        --Shak.
      -- {Las*civ"i*ous*ly}, adv. -- {Las*civ"i*ous*ness}, n.

Source : WordNet®

lasciviousness
     n : feeling morbid sexual desire [syn: {prurience}, {pruriency},
          {carnality}]