[1] : The Collaborative International Dictionary of English v.0.48

heartfelt \heart"felt`\ -fe^lt`, a.
   hearty; sincere.
   1913 webster

[2] : WordNet (r) 2.0

heartfelt
     adj : earnest; "one's dearest wish"; "devout wishes for their
           success"; "heartfelt condolences" syn: dear, devout,
            earnest
see also:
dear devout earnest 

[3] : Moby Thesaurus II by Grady Ward, 1.0

31 moby thesaurus words for "heartfelt":
   absorbing, acute, ardent, bona fide, committed, dedicated, deep,
   deep-felt, deepgoing, devoted, earnest, fervent, fervid, genuine,
   hearty, homefelt, honest, indelible, keen, passionate, penetrating,
   pervading, piercing, poignant, profound, serious, sharp, sincere,
   true, unfeigned, wholehearted

Heartfelt >> H Words
Heartfelt, definition of term: Heartfelt
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