Definitions of hickey:

• noun:   a temporary red mark on a person's skin resulting from kissing or sucking by their lover
• noun:   a small inflamed elevation of the skin; a pustule or papule; common symptom in acne
• noun:   something whose name is either forgotten or not known
• name:  A surname (common: 1 in 10000 families; popularity rank in the U.S.: #1173)