I'm no etymologist, but words fascinate me. Kardia, in many of its uses, has captivated my attention for a long time. As a Bible student, kardia appears multiple times as the Greek word for heart.
Not the organ that pumps blood through your body. Kardia is the figurative core of your being. It is the seat and center of human life, emotion, volitional will. It is the "causative source of one's psychological life in its various aspects." All that to say, your heart is a huge deal and deserves attention and care!