Source : Webster's Revised Unabridged Dictionary (1913)

Heartily \Heart"i*ly\, adv. [From {Hearty}.]
   1. From the heart; with all the heart; with sincerity.

            I heartily forgive them.              --Shak.

   2. With zeal; actively; vigorously; willingly; cordially; as,
      he heartily assisted the prince.

   {To eat heartily}, to eat freely and with relish. --Addison.

   Syn: Sincerely; cordially; zealously; vigorously; actively;
        warmly; eagerly; ardently; earnestly.