View source for Navel

{{Short description|Scarred area on the abdomen after detachment of the umbilical cord}}
{{Redirect|Belly button|other uses|Belly button (disambiguation)|and|Navel (disambiguation)}}
{{Redirect-multi|2|Innie|Outie}}
{{Human-centric|date=October 2024}}
{{Use dmy dates|date=August 2021}}
{{Infobox anatomy
|Name      = Navel

|Latin     = umbilicus
|Width     = 230
|Image     = File:2pi37vx04e9f1.webp
|Caption   = A human navel
|Precursor = [[Umbilical cord]]<br />[[Ductus venosus]]
|System    =
|Artery    = [[Umbilical artery]]
|Vein      = [[Umbilical vein]]
|Nerve     =
|Lymph     =
|image_size=}} 

The '''navel''' (clinically known as the '''umbilicus'''; {{plural form}}: '''umbilici''' or '''umbilicuses'''; also known as the '''belly button''' or '''tummy button''') is a protruding, flat, or hollowed area on the [[abdomen]] at the attachment site of the [[umbilical cord]].<ref>{{cite web|title=Definition of NAVEL|url=https://www.merriam-webster.com/dictionary/navel|website=Merriam-Webster|date=24 November 2023 |language=en}}</ref>

==Structure==
{{See also|Umbilical vein|Umbilical artery}}
[[File:Da Vinci Vitruve Luc Viatour.jpg|thumb|upright|The navel is the centre of the circle in this drawing of the ''[[Vitruvian Man]]'' by [[Leonardo da Vinci]].]]

The umbilicus is used to visually separate the abdomen into quadrants.<ref name="Openstax Anatomy & Physiology">{{cite web | url=http://cnx.org/content/col11496/latest/ | title=Anatomy & Physiology | date=25 April 2013 | publisher=Openstax college at Connexions | access-date=16 November 2013}}</ref>

The umbilicus is a prominent [[Scar#Umbilical|scar]] on the abdomen, with its position being relatively consistent among humans. The skin around the waist at the level of the umbilicus is supplied by the tenth thoracic [[spinal nerve]] (T10 [[dermatome (anatomy)|dermatome]]). The umbilicus itself typically lies at a vertical level corresponding to the junction between the L3 and L4 [[vertebrae]],<ref>{{cite book |last=Ellis |first=Harold |title=Clinical Anatomy: Applied Anatomy for Students and Junior Doctors |publisher=Wiley |location=New York |year=2006 |isbn=1-4051-3804-1 }}{{page needed|date=August 2015}}</ref> with a normal variation among people between the L3 and L5 vertebrae.<ref>{{cite book|last1=O'Rahilly|first1=Ronan|title=Basic Human Anatomy: A Regional Study of Human Structure|last2=Müller|first2=Fabiola|last3=Carpenter|first3=Stanley|last4=Swenson|first4=Rand|publisher=Dartmouth Medical School|year=2004|chapter=Abdominal walls|chapter-url=http://www.dartmouth.edu/~humananatomy/part_5/chapter_25.html|archive-url=https://archive.today/20120724132801/http://www.dartmouth.edu/~humananatomy/part_5/chapter_25.html|archive-date=24 July 2012|url-status=dead|access-date=10 November 2010}}</ref>

Parts of the adult navel include the "umbilical cord remnant" or "umbilical tip", which is the often protruding scar left by the detachment of the umbilical cord. This is located in the center of the navel, sometimes described as the ''belly button''. Around the cord remnant is the "umbilical collar", formed by the dense fibrous [[umbilical ring]]. Surrounding the umbilical collar is the periumbilical skin. Directly behind the navel is a thick fibrous cord formed from the umbilical cord, called the [[urachus]], which originates from the [[bladder]].<ref name=Parts>{{cite journal |last1=Khati |first1=Nadia J. |last2=Enquist |first2=Erik G. |last3=Javitt |first3=Marcia C. |title=Imaging of the Umbilicus and Periumbilical Region |journal=Radiographics |volume=18 |issue=2 |pages=413–4 |year=1998 |doi=10.1148/radiographics.18.2.9536487|pmid=9536487 }}</ref>

The belly button is unique to each individual due to its being a scar, and various general forms have been classified by medical practitioners.<ref>{{cite book |last=Shiffman |first=Melvin |title=Adult Umbilical Reconstruction: Principles and Techniques |publisher= Springer |location=Switzerland |year=2017 |isbn=978-3-319-43885-6 |page=53 |chapter=7.3 }}</ref><ref name=Types>{{cite book |last=Mohamed |first=Fahmy |chapter=Umbilicus Types and Shapes |publisher=Springer |location=Egypt |year=2018 |doi=10.1007/978-3-319-62383-2_22 |pages=105–8 |title=Umbilicus and Umbilical Cord |isbn=978-3-319-62382-5 }}</ref>{{Explain|date=November 2021}}

*'''Outie''': A navel consisting of the umbilical tip protruding past the periumbilical skin is an outie. Essentially any navel which is not concave.
**'''Swirly/spiral''': A rare form in which the umbilical cord scar forms a swirl shape.
**'''Split''': The protruding umbilical cord scar extends outwards, but is cleft in two by a fissure which extends part or all the way through the umbilical cord scar. This form is similar in appearance to a coffee bean.
**'''Protrusion''': The umbilical cord remnant is completely divulged, exposing the full umbilical scar.
**'''Circlet''': Although the entirety of the umbilical cord remnant sits out with the umbilical collar, the centre of the knot is inset by a deep fissure. Unlike a split outie, in this form the fissure is contained centrally and does not extend past the umbilical cord remnant in any direction, much akin to a 'donut' shape.<ref>{{cite book |last=Stephen Cullen |first=Thomas |title=Umbilicus |chapter-url=https://archive.org/details/embryologyanatom00culluoft |publisher= W.B.Saunders Company |location=Australia |year=1916 |isbn=978-0-7334-2609-4 |page=1.1–1.7 |chapter=2 }}</ref>
*'''Innie''': A navel in which the umbilical tip does not protrude past the periumbilical skin. Any navel which is concave.
**'''Round''': Round navels are completely circular with no hooding.
**'''Vertical''': Some navels present in the form of a more elongate hollow parallel with the [[Linea alba (abdomen)|linea alba]].
**'''Oval''': This form consists of three variants; superior hooding, inferior hooding, no hooding.
**'''T-shaped''': As the name states, the scar is in the shape of a T, and may have superior hooding to various extent.
**'''Horizontal''': The scar is the least visible, as the natural lines of the [[tendinous intersection]] fold over the scar.
*'''Distorted''': Any navel which does not fit well into any of the other categories.

<gallery widths="200" heights="200">
File:T-shaped navel.jpg|A "T"-shaped "innie" navel
File:Female Outie 2.jpg|An outie navel
</gallery>

==Clinical significance==
[[File:Femalelaparoscopic.jpg|thumb|alt=The navel of a female after a laparoscopic procedure.|The navel of a female after a [[Laparoscopy|laparoscopic procedure]]]]

===Disorders===
Outies are sometimes mistaken for [[umbilical hernia]]s; however, they are a completely different shape with no health concern, unlike an umbilical hernia. The navel (specifically abdominal wall) would be considered an umbilical hernia if the protrusion were 5 [[centimeter]]s or more. The diameter of an umbilical hernia is usually 1/2-inch or more.<ref name="pmid11369993">{{cite journal |last1=Meier |first1=Donald E. |last2=OlaOlorun |first2=David A. |last3=Omodele |first3=Rachael A. |last4=Nkor |first4=Sunday K. |last5=Tarpley |first5=John L. |title=Incidence of Umbilical Hernia in African Children: Redefinition of 'Normal' and Reevaluation of Indications for Repair |journal=World Journal of Surgery |volume=25 |issue=5 |pages=645–8 |year=2001 |pmid=11369993 |doi=10.1007/s002680020072 |s2cid=22628578 }}</ref> While the shape of the human navel may be affected by long term changes to diet and exercise, unexpected change in shape may be the result of [[ascites]].<ref>{{cite web |first=Steven K. |last=Herrine |title=Ascites |url=http://www.merckmanuals.com/home/liver_and_gallbladder_disorders/manifestations_of_liver_disease/ascites.html |publisher=[[The Merck Manuals]]}}</ref> 
{{clear left}}
In addition to change in shape being a possible side effect from ascites and umbilical hernias, the navel can be involved in umbilical [[sinus (anatomy)|sinus]] or fistula, which in rare cases can lead to menstrual or fecal discharge from the navel. Menstrual discharge from the umbilicus is a rare disorder associated with umbilical [[endometriosis]].<ref name="BagadeGuirguis2009">{{cite journal |last1=Bagade |first1=Pallavi V |last2=Guirguis |first2=Mamdouh M |title=Menstruating from the umbilicus as a rare case of primary umbilical endometriosis: a case report |journal=Journal of Medical Case Reports |volume=3 |page=9326 |year=2009 |pmid=20062755 |pmc=2803849 |doi=10.1186/1752-1947-3-9326 |doi-access=free }}</ref>

===Other disorders===
*[[Omphalitis]], an inflammatory condition of the umbilicus in the [[neonate|newborn]], usually caused by a bacterial infection.<ref>{{cite book |last=Cunningham|first = F. |title=Williams Obstetrics: The Newborn |publisher=McGraw-Hill |edition=24th }}</ref><ref>Fleisher, Gary R. Textbook of Pediatric Emergency Medicine. Philadelphia: Lippincott Williams & Wilkins, 2006, p.&nbsp;928.</ref>
* Omphalophobia is the fear of belly buttons. People suffering from omphalophobia are terrified of belly buttons—their own or, in some cases, those of others. They do not like touching their belly buttons (or other people touching them). Sometimes just seeing a belly button is enough to make them feel disgusted or terrified.<ref>{{Cite web |title=Omphalophobia Fear of Belly Buttons |url=https://www.tranceformpsychology.com/phobias/omphalophobia.html#:~:text=Omphalophobia%20is%20the%20Fear%20of,,%20the%20fear%20of%20deformity.) |access-date=2025-02-05 |website=Tranceform Psychology |language=en-GB}}</ref>

===Surgery===
To minimize scarring, the navel is a recommended site of incision for various surgeries, including transgastric [[Appendectomy|appendicectomy]],<ref>{{cite journal |last1=Kaehler |first1=G. |last2=Schoenberg |first2=M. B. |last3=Kienle |first3=P. |last4=Post |first4=S. |last5=Magdeburg |first5=R. |title=Transgastric appendicectomy |journal=British Journal of Surgery |volume=100 |issue=7 |pages=911–5 |year=2013 |pmid=23575528 |doi=10.1002/bjs.9115 |s2cid=24285562 |doi-access=free}}
*{{cite news |author=Sarah Glynn |date=12 April 2013 |title=Scarless Surgery Through The Navel Feasible Alternative For Appendicitis |work=Medical News Today |url=http://www.medicalnewstoday.com/articles/259007.php}}</ref> [[gall bladder]] surgery,<ref>{{cite press release|title=SRMC Surgeon Offers Gallbladder Removal through Belly Button Incision with da Vinci System|publisher=Southeastern Health|date=9 December 2013|url=http://www.srmc.org/main/aboutfastfact/aboutnewsarticles/892-srmc-surgeon-offers-gallbladder-removal-through-belly-button-incision-with-da-vincir-system.html|access-date=16 August 2015|archive-url=https://archive.today/20150104162519/http://www.srmc.org/main/aboutfastfact/aboutnewsarticles/892-srmc-surgeon-offers-gallbladder-removal-through-belly-button-incision-with-da-vincir-system.html|archive-date=4 January 2015|url-status=dead}}</ref> and the [[umbilicoplasty]]<ref>{{cite journal |last1=Bruekers |first1=Sven E. |last2=van der Lei |first2=Berend |last3=Tan |first3=Tik L. |last4=Luijendijk |first4=Roland W. |last5=Stevens |first5=Hieronymus P. J. D. |title='Scarless' Umbilicoplasty |journal=Annals of Plastic Surgery |volume=63 |issue=1 |pages=15–20 |year=2009 |pmid=19546666 |doi=10.1097/SAP.0b013e3181877b60 |s2cid=206034192 }}</ref> procedure itself.

==Other animals==
All [[Placentalia|placental]] [[mammal]]s have a navel, although it is generally more conspicuous in humans.<ref>{{cite book|author=Mohamed Fahmy|title= Umbilicus and Umbilical Cord|url= https://books.google.com/books?id=8N9LDwAAQBAJ&pg=PA6|access-date=7 December 2024|year=2018|publisher=Springer International Publishing|isbn= 978-3-31962-383-2}}</ref>

==Fashion, society and culture==
{{Further|Cultural views on the navel}}
[[File:Yosakoi Performers at Kochi Yosakoi 2006 17.jpg|thumb|Japanese women performing a traditional Japanese dance ''{{lang|ja-latn|[[Yosakoi]]|italic=no}}'' in navel-exposing attire in the ''{{lang|ja-latn|[[Yosakoi Matsuri]]|italic=no}}'' 2006 at [[Kōchi, Kōchi|Kōchi]].]]
The public exposure of the male and female [[midriff]] and bare navel was considered [[taboo]] at times in the past in [[Western culture]]s, being considered [[Modesty|immodest]] or [[indecent exposure|indecent]]. Female navel exposure was banned in some jurisdictions, but community perceptions have changed to this now being acceptable.<ref name="news">{{cite news|title=New code may reveal navel |url=https://news.google.com/newspapers?id=eLtPAAAAIBAJ&pg=3939,2026891&dq=navel+reveal |access-date=20 April 2012 |newspaper=Mohave Daily Miner |date=24 March 1985}}</ref> The [[crop top]] is a shirt that often exposes the belly button and has become more common among young people.<ref>{{Cite news |title=Men in crop tops seem to be trending thanks to Kid Cudi, the social media and the catwalk |website=The Independent |url=https://www.independent.co.uk/life-style/fashion/features/men-s-crop-top-seem-to-be-trending-thanks-to-kid-cudi-the-social-media-and-the-catwalk-9678555.html |url-status=live |url-access=subscription |access-date=30 January 2019 |archive-url=https://ghostarchive.org/archive/20220618/https://www.independent.co.uk/life-style/fashion/features/men-s-crop-top-seem-to-be-trending-thanks-to-kid-cudi-the-social-media-and-the-catwalk-9678555.html |archive-date=18 June 2022}}</ref> Exposure of the male navel has rarely been stigmatised and has become particularly popular in recent years, due to the strong resurgence of the male crop top and male [[navel piercing]].<ref name="Crop">{{cite web |last=Ktena |first=Natalie |date=28 August 2018 |title=We talked to a 'crop top historian' about the comeback of the male crop top |url=https://www.bbc.co.uk/bbcthree/article/a8a41390-c35c-44be-b868-c7947211ea2e |access-date=14 September 2018 |newspaper=BBC}}</ref> The navel and midriff are often also displayed in [[bikini]]s, or when [[low-rise pants]] are worn.

While the West was relatively resistant to navel-baring clothing until the 1980s, it has long been a fashion with [[India]]n women,<ref name="Mukulika">Banerjee, Mukulika & Miller, Daniel (2003) ''The Sari''. Oxford; New York: Berg {{ISBN|1-85973-732-3}}{{page needed|date=August 2015}}</ref> often displayed with [[sari]]s or [[lehenga]]s.

The [[Japanese people|Japanese]] have long had a special regard for the navel. During the early [[Jōmon period]] in northern Japan, three small balls indicating the breasts and navel were pasted onto flat clay objects to represent the female body. The navel was exaggerated in size, informed by the belief that the navel symbolized the center where life began.<ref>{{cite book |chapter=First Indications of Symbolic Expression |pages=114–5 |chapter-url=https://books.google.com/books?id=Yrla4QyhFasC&pg=PA114 |first=Nelly |last=Naumann |author-link=Nelly Naumann |year=2000 |title=Japanese Prehistory: The Material and Spiritual Culture of the Jōmon Period |publisher=Otto Harrassowitz Verlag |isbn=978-3-447-04329-8}}</ref>

In Arabic-[[Levant]]ine culture, [[Belly dance|belly dancing]] is a popular art form that consists of dance movements focused on the torso and navel.<ref>{{Cite web|url=https://www.bellydance.org/articles/bellydance_history/|title=Belly Dance History – A History of Belly Dancing « Belly Dance org|website=bellydance.org|access-date=2018-12-24}}</ref>

[[Buddhism]] and [[Hinduism]] refer to the [[chakra]] of the navel as the [[manipura]]. In [[qigong]], the navel is seen as the main energy centre, or [[dantian]]. In [[Hinduism]], the [[Kundalini|Kundalini energy]] is sometimes described as being located at the navel.

==See also==
* [[Alvinolagnia]]
* [[Navel fetishism]]
* [[Navel piercing]]
* [[Omphalos]]
* [[Skin flora#Umbilical microbiome|Umbilical microbiome]]
* [[Omphaloskepsis]]

== References ==
{{Reflist}}

== Further reading ==
* {{Cite web |url = http://navels.yourwildlife.org |title = Belly Button Biodiversity Project |access-date = 15 April 2020 |archive-url = https://web.archive.org/web/20160730002157/http://navels.yourwildlife.org/ |archive-date = 30 July 2016 |url-status = dead }}
* {{Cite journal |last1=Craig |first1=Stefan B. |last2=Faller |first2=Mary S. |last3=Puckett |first3=Charles L. |title=In Search of the Ideal Female Umbilicus |journal=Plastic and Reconstructive Surgery |volume=105 |issue=1 |pages=389–92 |year=2000 |pmid=10627008 |doi=10.1097/00006534-200001000-00062 }}
* {{Cite journal |last1=Gabriele |first1=Raimondo |last2=Conte |first2=Marco |last3=Egidi |first3=Federico |last4=Borghese |first4=Mario |title=Umbilical metastases: current viewpoint |journal=World Journal of Surgical Oncology |volume=3 |issue=1 |pages=13 |year=2005 |pmid=15723695 |pmc=552325 |doi=10.1186/1477-7819-3-13 |doi-access=free }}
* {{Cite journal |last1=Moreau |first1=Corrie S. |last2=Hulcr |first2=Jiri |last3=Latimer |first3=Andrew M. |last4=Henley |first4=Jessica B. |last5=Rountree |first5=Nina R. |last6=Fierer |first6=Noah |last7=Lucky |first7=Andrea |last8=Lowman |first8=Margaret D. |last9=Dunn |first9=Robert R. |title = A Jungle in There: Bacteria in Belly Buttons are Highly Diverse, but Predictable |journal=PLOS ONE|volume=7 |issue=11 |pages=e47712 |year=2012 |pmid=23144827 |pmc=3492386 |doi=10.1371/journal.pone.0047712 |bibcode=2012PLoSO...747712H |doi-access=free }}
* {{Cite journal |last1=Piskun |first1=Gregory |last2=Rajpal |first2=Sanjeev |title=Transumbilical Laparoscopic Cholecystectomy Utilizes No Incisions Outside the Umbilicus |journal=Journal of Laparoendoscopic & Advanced Surgical Techniques |volume=9 |issue=4 |pages=361–4 |year=1999 |pmid=10488834 |doi=10.1089/lap.1999.9.361 }}
* {{Cite web |title=New meaning to 'navel-gazing': Scientists study belly button bacteria|date=14 April 2011|url=http://bodyodd.nbcnews.com/_news/2011/04/14/6466035-new-meaning-to-navel-gazing-scientists-study-belly-button-bacteria|url-status=dead|archive-url=https://archive.today/20160726085907/http://bodyodd.nbcnews.com/_news/2011/04/14/6466035-new-meaning-to-navel-gazing-scientists-study-belly-button-bacteria|publisher=[[NBC News]]|archive-date=26 July 2016|work=Body Odd|access-date=16 August 2015}}

== External links ==
* {{Commons category-inline}}

{{Human anatomical features}}
{{Authority control}}

[[Category:Abdomen]]
[[Category:Scarring]]
[[Category:Navel]]