It depends on the region of the United States. In Latin America, that is a part of the body we can not understand. In the west, it is a wonderful hippocampus. In the east, this is a sigh. It can also be used as words of emotion
From the TV program SpongeBob SquarePants it evolves to a sexual cue around the terminology and eventually become a nickname for genitals (usually also male, but also to women), or ejaculation