Heart Defined

Heart: a hollow, muscular organ in the thorax which maintains the circulation of the blood through the blood vessels; this organ considered as the seat of the affections, passions, and emotions, as distinguished from the intellect and will; hence, tenderness, sympathy, affection; also, courage, spirit, energy; sweetheart, beloved, used as a term of endearment; a bold or brave man, used in affectionate commendation; one's secret thoughts, innermost soul, conscience; one's personality as a vital or active force; as to love with one's whole heart; the vital, inner or chief part of anything; the center; core.
From The Winston Simplified Dictionary, copyright 1933