Source : Webster's Revised Unabridged Dictionary (1913)

Intone \In*tone"\, v. t. [imp. & p. p. {Intoned}; p. pr. & vb.
   n. {Intoning}.] [LL. intonare, intonatum; pref. in- in + L.
   tonus tone. See {Tone} and cf. {Entune}, {Intonate}.]
   To utter with a musical or prolonged note or tone; to chant;
   as, to intone the church service.