The heart is a muscular organ in humans and other animals, which pumps blood through the blood vessels of the circulatory system. Blood provides the body with oxygen and nutrients, as well as assists in the removal of metabolic wastes.
In humans, the heart is located between the lungs, in the middle compartment of the chest.
In Scripture, when the word “heart” is used, it usually refers to the human spirit. An example of this is Romans 10:9, “That if you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved.” However, in everyday contemporary communication, the word could refer to the core of something, courage and even an inclination or tendency of a certain kind.