Editing Hair (section)

==Overview==
===Meaning===
[[File:506 Hair.jpg|thumb|Anatomy of the hair shaft and bulb.]]
The word "hair" usually refers to two distinct structures: 
#the part beneath the skin, called the [[hair follicle]], or, when pulled from the skin, the bulb or root. This organ is located in the [[dermis]] and maintains [[stem cell]]s, which not only re-grow the hair after it falls out, but also are recruited to regrow skin after a [[wound]].<ref>{{cite journal|last1= Krause|first1= K|last2= Foitzik|first2= K|title= Biology of the Hair Follicle: The Basics|journal= Seminars in Cutaneous Medicine and Surgery|volume= 25|issue= 1|pages= 2–10|year= 2006|doi= 10.1016/j.sder.2006.01.002|doi-broken-date= 1 November 2024|pmid= 16616298| issn=1085-5629}}</ref>
# the hair shaft, which is the hard filamentous part that extends above the skin surface. It is made of multi-layered keratinized (dead) flat cells whose rope-like filaments provide structure and strength to it. The protein called [[keratin]] makes up most of its volume. A cross section of the hair shaft may be divided roughly into three zones.

Hair fibers have a structure consisting of several layers, starting from the outside:
# the [[Cuticle (hair)|cuticle]], which consists of several layers of flat, thin cells laid out overlapping one another as roof shingles
# the [[Cortex (hair)|cortex]], which contains the [[keratin]] bundles in cell structures that remain roughly rod-like
# the [[Medulla (hair)|medulla]], a disorganized and open area at the fiber's center<ref>{{cite book|author=Feughelman, Max|url=https://books.google.com/books?id=PSNIYKwKu8kC|title=Mechanical Properties and Structure of Alpha-keratin Fibres: Wool, Human Hair and Related Fibres|publisher=UNSW Press|year=1997|isbn=978-0-86840-359-5|access-date=27 January 2016}}</ref>

===Etymology===
The word "hair" is derived from {{langx|enm|heer}} and {{lang|enm|hêr}}, in turn derived from {{langx|ang|hǽr}} and {{lang|ang|hér}}, with influence from {{langx|non|hár}}. Both the Old English and Old Norse words derive from {{langx|gem-x-proto|hēran}} and are related to terms for hair in other Germanic languages such as {{langx|sv|hår}}, [[Dutch language|Dutch]] and {{langx|de|haar}}, and {{langx|ofs|her}}.<ref>{{cite web |title=hair - Etymology of hair by etymonline |url=https://www.etymonline.com/word/hair#etymonline_v_1377 |website=www.etymonline.com |language=en|access-date=20 July 2024}}</ref><ref>{{cite web |title=hair |url=https://www.oed.com/dictionary/hair_n?tab=factsheet#2190694 |website=OED |access-date=20 July 2024}}</ref> The now broadly obsolete word "fax" refers specifically to head hair and is found in compounds such as [[Fairfax (name)|Fairfax]] and [[Halifax, West Yorkshire|Halifax]]. It is derived from {{langx|ang|feax}} and is cognate with terms such as [[Old Norse]] and {{langx|no|fax}}.<ref>{{cite web |title=fax |url=https://www.oed.com/dictionary/fax_n1?tab=factsheet |website=OED |access-date=20 July 2024}}</ref>