heartfelt

genuine in feeling <a number of the retiring teacher's former students have expressed their heartfelt appreciation for the invaluable lessons they learned in his classroom> Synonyms sincere, unfeignedRelated Words unaffected, unforced; artless, honest, ingenuous, translucent, transparent, true; authentic, genuine; hearty, wholehearted, whole-souledNear Antonyms backhanded, double-dealing, hypocritical, left-handed, mealy, mealymouthed, two-faced, unctuousAntonyms affected, artificial, false, feigned, insincere