A hollow muscular organ that pumps the blood through the circulatory system by rhythmic contraction and dilation. In vertebrates there may be up to four chambers (as in humans), with two atria and two ventricles. The central or innermost part of something. A conventional representation of a heart with two equal curves meeting at a point at the bottom and a cusp at the top. The condition of agricultural land as regards fertility. Like very much; love.