|an informal name for the navel|
bellybutton bel·ly·but·ton (běl'ē-bŭt'n)
belly button definition
in anatomy, a small depression in the abdominal wall at the point of attachment of the umbilical cord (q.v.). It indicates the point through which the mammalian fetus obtained nourishment from its mother through the blood vessels of the umbilical cord.
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