Merriam-Webster's Collegiate® Dictionary, 11th Edition
HEART
I. noun
Etymology: Middle English hert, from Old English heorte; akin to Old High German herza heart, Latin cord-, cor, Greek kardia Date: before 12th century
1. a hollow muscular organ of vertebrate animals that by its rhythmic contraction acts as a force pump maintaining the circulation of the blood, a structure in an invertebrate animal functionally analogous to the vertebrate heart, breast , bosom , something resembling a heart in shape,
2. a playing card marked with a stylized figure of a red heart, the suit comprising cards marked with hearts, a game in which the object is to avoid taking tricks containing hearts,
3. personality , disposition , intellect , the emotional or moral as distinguished from the intellectual nature: as, generous disposition ; compassion , love , affections , courage , ardor , one's innermost character, feelings, or inclinations ,
6. the central or innermost part ; center , the essential or most vital part of something, the younger central compact part of a leafy rosette (as a head of lettuce),
II. transitive verb Date: before 12th century hearten , to fix in the heart