Black Haired Girl On The Chair With A Navel Tattoo

Some people have a smooth indentation instead of an "innie" or "outie", usually due to surgery for umbilical hernia, gastroschisis, or tummy tuck. Overweight individuals have larger belly buttons on average than those of normal weight.
Fashion
Fashion sometimes exploits the navel through clothing that leaves part of the lower abdomen (i.e. the midriff) bare, a usage that is much more common for women than for men. Displaying a bare navel has been a taboo in certain Western cultures: for example, in the 1960s, Barbara Eden was not allowed to show her navel on the TV show I Dream of Jeannie. It is now generally considered acceptable in Western culture.