heart vs feeling

heart and feeling both are nouns.

Word	Noun	Adjective	Verb	Adverb
heart	Yes	No	No	No
feeling	Yes	No	No	No

As nouns, feeling is a hypernym of heart; that is, feeling is a word with a broader meaning than heart:

heart (noun)	feeling (noun)
a playing card in the major suit that has one or more red hearts on it	the experiencing of affective and emotional states
the courage to carry on	an intuitive understanding of something
an inclination or tendency of a certain kind	a physical sensation that you experience
the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body	the sensation produced by pressure receptors in the skin
the locus of feelings and intuitions	a vague idea in which some confidence is placed
the choicest or most essential or most vital part of some idea or experience	the general atmosphere of a place or situation and the effect that it has on people
a positive feeling of liking
a firm rather dry variety meat (usually beef or veal)
an area that is approximately central within some larger region
a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines