Source : Webster's Revised Unabridged Dictionary (1913)

Intonation \In`to*na"tion\, n. [See 1st {Intonate}.]
   A thundering; thunder. [Obs.] --Bailey.

Intonation \In`to*na"tion\, n. [Cf. F. intonation. See
   {Intone}.] (Mus.)
   (a) The act of sounding the tones of the musical scale.
   (b) Singing or playing in good tune or otherwise; as, her
       intonation was false.
   (c) Reciting in a musical prolonged tone; intonating, or
       singing of the opening phrase of a plain-chant, psalm, or
       canticle by a single voice, as of a priest. See {Intone},
       v. t.

Source : WordNet®

intonation
     n 1: rise and fall of the voice pitch [syn: {modulation}, {pitch
          contour}]
     2: singing by a soloist of the opening piece of plainsong
     3: the act of singing in a monotonous tone [syn: {chanting}]
     4: the production of musical tones (by voice or instrument);
        especially the exactitude of the pitch relations