Source : Webster's Revised Unabridged Dictionary (1913)

Assonance \As"so*nance\, n. [Cf. F. assonance. See {Assonant}.]
   1. Resemblance of sound. ``The disagreeable assonance of
      `sheath' and `sheathed.''' --Steevens.

   2. (Pros.) A peculiar species of rhyme, in which the last
      acce`ted vow`l and tnose whioh follow it in one word
      correspond in sound with the vowels of another word, while
      the consonants of the two words are unlike in sound; as,
      calamo and platano, baby and chary.

            The assonance is peculiar to the Spaniard. --Hallam.

   3. Incomplete correspondence.

            Assonance between facts seemingly remote. --Lowell.

Source : WordNet®

assonance
     n : the repetition of similar vowels in the stressed syllables
         of successive words [syn: {vowel rhyme}]