The navel (clinically known as the umbilicus, colloquially known as the belly button) is a scar on the abdomen at the attachment site of the umbilical cord. All placental mammals have a navel, and it is quite conspicuous in humans. Other animals' navels tend to be smoother and flatter, often nothing more than a thin line, and are often obscured by fur as well.

The umbilicus is a prominent mark on the abdomen, with its position being relatively consistent amongst humans. The skin around the waist at the level of the umbilicus is supplied by the tenth thoracic spinal nerve (T10 dermatome). The umbilicus itself typically lies at a vertical level corresponding to the junction between the L3 and L4 vertebrae, with a normal variation among people between the L3 and L5 vertebrae. The umbilicus forms a visible depression on the skin of the abdomen, and the underlying abdominal muscle layers also present a concavity; thinness at this point contributes to a relative structural weakness, making it susceptible to hernia.^{[citation needed]} During pregnancy, the uterus presses the navel of the pregnant woman outward, however it usually retracts after birth.

Sanaya Irani (born on 17 September)^{[citation needed]} is an Indian television actress known for her roles in television series such as Left Right Left, Radhaa Ki Betiyaan Kuch Kar Dikhayengi, Miley Jab Hum Tum and Iss Pyaar Ko Kya Naam Doon. She currently plays the lead role of Khushi Kumari Gupta Singh Raizada in Iss Pyaar Ko Kya Naam Doon? on Star Plus.

Sanaya was born and raised in Mumbai, Maharashtra, and received her schooling in Ooty. She appeared in various advertisements and modelling. She made her performing debut with Jagjit Singh's song "Tumko Dekha To Yeh", then appeared in other music videos^{[citation needed]}. For almost four years, Sanaya continued doing commercials and music videos.She is the most loved actress on Indian Television and has been titled Television Barbie Doll^{[citation needed]}

After her stint with modeling she entered acting, in the role of Kajol's friend in the movie Fanaa (2006). She then went on to play the role of Sameera in Left Right Left, her first show on the Indian Channel SAB TV. She then had a role as Sanaya in Radhaa Ki Betiyaan Kuch Kar Dikhayengi on Imagine TV. Her breakout^{[citation needed]} role was as Gunjan on Miley Jab Hum Tum. She hosted Zara Nachke Dikha Season 2 on Star One . Currently she is playing the lead role of Khushi in Iss Pyaar Ko Kya Naam Doon?, a daily soap on STAR Plus. She is currently dating her previous co-star from Miley Jab Hum Tum, Mohit Sehgal.