RACooper beat me to it... but I'll pretend otherwise.
naˇvel
n.
The mark on the surface of the abdomen that indicates where the umbilical cord was attached to the fetus during gestation. Also called bellybutton, umbilicus.
Source: The American HeritageŽ Dictionary
naˇval
adj.
1. Of or relating to ships or shipping. See Synonyms at nautical.
2. Of or relating to a navy.
3. Having a navy: a great naval power.
Source: The American HeritageŽ Dictionary
Fear the tummy armada?
Here's what one person does with theirs.