Editing Anatomical terms of location (section)

==Main terms==
{{Anchor|superior|inferior}}
{{See also|Anatomical terminology#Standard terms}}

===Superior and inferior===
In the [[standard anatomical position|standard human anatomical position]], '''superior''' ({{ety|la|super|above}}) or '''cranial''', describes something that is nearer to the head, and '''inferior''' ({{ety|la|inferus|below}}) or '''caudal''' describes what is below, and nearer to the feet.<ref name="libre3"/> Examples are the [[superior mediastinum]], and [[inferior mediastinum]]. Neuroanatomy examples are the [[superior colliculus]], and the [[inferior colliculus]].<ref name="Moore1">{{cite book |last1=Moore |first1=Keith L. |last2=Dalley |first2=Arthur F. |last3=Agur |first3=Anne M. R. |title=Clinically oriented anatomy |date=2018 |publisher=Wolters Kluwer |location=Philadelphia Baltimore New York London Buenos Aires Hong Kong Sydney Tokyo |isbn=9781496347213 |pages=5–8 |edition=Eighth}}</ref> In veterinary anatomy, the terms superior and inferior are not used except to describe the eye, eyelids, lips and inner ear, using instead '''dorsal''' and '''ventral'''.<ref name="Dyce2010"/>

===Anterior and posterior===
{{Redirect|Anterior}}<!-- [[Posterior]] is a dab page, not redirect -->

'''Anterior''' ({{ety|la|ante|before}}) describes what is in front, and '''posterior''' ({{ety|la|post|after}}) describes what is to the back of something.<ref name="Purves1">{{cite web |last1=Purves |first1=Dale |last2=Augustine |first2=George J. |last3=Fitzpatrick |first3=David |last4=Katz |first4=Lawrence C. |last5=LaMantia |first5=Anthony-Samuel |last6=McNamara |first6=James O. |last7=Williams |first7=S. Mark |title=Some Anatomical Terminology |url=https://www.ncbi.nlm.nih.gov/books/NBK10971/ |website=Neuroscience. 2nd edition |publisher=Sinauer Associates |access-date=7 March 2025 |language=en |date=2001}}</ref> For example, for many [[fish]] the [[gill]] openings are posterior to the eyes and anterior to the tail.

===Dorsal and ventral===
These two terms, used in [[Veterinary medicine|veterinary anatomy]], are also used in [[human anatomy]] mostly in  [[neuroanatomy]], and [[embryology]], to describe something at the back (dorsal, posterior) or front (ventral, anterior) of an organ, or organism.<ref name="Gray2016"/><ref name="Purves1"/>

The '''dorsal''' ({{ety|la|dorsum|back}}) surface, (also '''dorsum''') of an organism or [[organ (biology)|organ]], refers to the back, or upper side, such as in the human, the dorsum of the [[tongue]], the [[dorsum of hand|dorsum of the hand]], and the [[dorsum of foot|dorsum of the foot]].  If talking about the skull, the dorsal side is the top.<ref name="amigo2"/><ref name="Moore1"/>

{{anchor|inserted2020-09-25specificallyfor ventral}}
The '''ventral''' ({{ety|la|venter|belly}}) surface refers to the front, or lower side, of an organism, or organ such as the undersurface of the tongue.<ref name="amigo2"/>

In a [[fish]], the [[dorsal fin]] is on the upper surface and its [[ventral fin]]s (pelvic fins) are on the belly or undersurface.<ref name="SCDNR">{{cite web |title=SCDNR - Fishing Information |url=https://www.dnr.sc.gov/fish/anatomy.html |website=www.dnr.sc.gov |access-date=27 February 2025}}</ref>

The terms are used in other contexts, for example in [[gun turret#Aircraft layout|dorsal and ventral gun turrets]] on a bomber aircraft.

{{Anchor|medial|median|lateral}}

===Medial and lateral<span class="anchor" id="unilateral"></span><span class="anchor" id="bilateral"></span><span class="anchor" id="temporal"></span>===
These terms describe how close something is to the median plane.<ref name="Gray's"/><ref name="Purves1"/> '''Lateral''' ({{ety|la|lateralis|to the side}}) describes something to the sides of an animal, as in "left lateral" and "right lateral". '''Medial''' ({{ety|la|medius|middle}}) describes structures close to the median plane, or closer to the median plane than another structure.<ref name="Purves1"/> For example, in a human, the arms are lateral to the [[torso]]. The [[Sex organ|genitals]] are medial to the legs. '''Temporal''' has a similar meaning to lateral but is restricted to the head.

The terms "left" and "right", or [[sinistral and dextral]], refer to the halves of a bilaterally symmetrical body divided by the median plane.

Terms derived from lateral include:

* '''Contralateral''' ({{ety|la|contra|against}}): on the side opposite to another structure. For example, the right arm and leg are controlled by the left, [[Contralateral brain|contralateral, side of the brain]].
* '''Ipsilateral''' ({{ety|la|ipse|same}}): on the same side as another structure. For example, the left arm is ipsilateral to the left leg.<ref name="Moore1"/>
* '''Bilateral''' ({{ety|la|bis|twice}}): on both sides of the body.<ref name="Moore1"/> For example, bilateral [[orchiectomy]] means removal of [[testes]] on both sides of the body.
* '''Unilateral''' ({{ety|la|unus|one}}) one-sided or single-sided: on one side of the body.<ref name="Moore1"/> For example, unilateral deafness is hearing impairment in one ear.<ref name="Dodson">{{cite journal |last1=Dodson |first1=Kelley M |last2=Georgolios |first2=Alexandros |last3=Barr |first3=Noelle |title=Etiology of unilateral hearing loss in a national hereditary deafness repository |journal=American Journal of Otolaryngology |date=2012 |volume=33 |issue=5 |pages=590-594 |doi=10.1016/j.amjoto.2012.03.005 |access-date=24 March 2025| url=https://www.sciencedirect.com/science/article/pii/S0196070912000658|doi-access=free }}</ref>

'''[[Varus deformity|Varus]]''' ({{ety|la||bow-legged}}) and '''[[valgus deformity|valgus]]''' ({{ety|la||knock-kneed}} ) are terms used to describe angulation or bowing  of a bone or joint within the coronal plane, where the distal portion deviates towards (varus) or away from (valgus) the midline.<ref>{{cite web |last1=Hacking |first1=Craig |title=Valgus vs varus |url=https://radiopaedia.org/articles/valgus-vs-varus-1?lang=us |website=Radiopedia |access-date=24 March 2025}}</ref>

{{Anchor|proximal|distal}}

===Proximal and distal===
{{Redirect2|Proximal|distal|the linguistic terms|Demonstrative#Distal and proximal demonstratives|the dental terms|Glossary of dentistry}}
[[File:Blausen 0019 AnatomicalDirectionalReferences.png|thumb|upright=1.3|Anatomical directional reference]]
{{wiktionary | proximal | distal}}

The terms '''proximal''' ({{ety|la|proximus|nearest}}) and '''distal''' ({{ety|la|distare|to stand away from}}) are used to describe parts of a feature that are close to or distant from the main mass of the body, respectively.<ref name="Seer2025">{{cite web |title=Anatomical Terminology {{!}} SEER Training |url=https://training.seer.cancer.gov/anatomy/body/terminology.html |website=training.seer.cancer.gov |access-date=10 March 2025}}</ref> Thus the upper arm in humans is proximal and the hand is distal. The main mass is taken as the center, the [[chest]], or the [[heart]].<ref name="meaning"/>

"Proximal and distal" are frequently used when describing [[appendage]]s, such as [[fins]], [[tentacle]]s, and [[Limb (anatomy)|limbs]]. Although the direction indicated by "proximal" and "distal" is always respectively towards or away from the point of attachment, a given structure can be either proximal or distal in relation to another point of reference. Thus the elbow is distal to a wound on the upper arm, but proximal to a wound on the lower arm.<ref name="meaning">{{cite web |title=What do distal and proximal mean? |website=The Survival Doctor |url= http://www.thesurvivaldoctor.com/2011/10/04/what-do-distal-and-proximal-mean/ |access-date= 2016-01-07|date=2011-10-05 }}</ref>

This terminology is also employed in molecular biology and therefore by extension is also used in chemistry, specifically referring to the atomic loci of molecules from the overall [[Moiety (chemistry)|moiety]] of a given compound.<ref>{{cite journal|last1= Singh|first1= S |title=Chemistry, design, and structure-activity relationship of cocaine antagonists |journal=Chemical Reviews|date=8 March 2000|volume=100|issue=3|pages=925–1024|pmid= 11749256 |doi= 10.1021/cr9700538}}
</ref>

{{Anchor|caudal|cranial|rostral}}

===Rostral, cranial, and caudal===
[[File:Rostralcaudal.svg|thumb|right|In the [[human skull]], the terms ''rostral'' and ''caudal'' are adapted to the curved [[neuraxis]] of [[Hominidae]], ''rostrocaudal'' meaning the region on C shape connecting rostral and caudal regions.]]

Specific terms exist to describe how close or far something is to the head or tail of an animal. To describe how close to the head of an animal something is, three distinct terms are used:

* '''Rostral''' ({{ety|la|rostrum|beak, nose}}) describes something situated toward the oral or nasal region, or in the case of the brain, toward the tip of the frontal lobe.<ref name="Moore1"/><ref name="Purves1"/>
* '''Cranial''' ({{ety|el|κρανίον|skull}}) or '''cephalic''' ({{ety|el|κεφαλή|head}}) describes how close something is to the head of an organism.<ref name="Moore1"/>
* '''Caudal''' ({{ety|la|cauda|tail}}) describes how close something is to the trailing end of an organism.<ref name="Purves1"/>

These terms are generally preferred in veterinary medicine and not used as often in human medicine.<ref name="Hickman et al. 2003">Hickman, C. P. Jr., Roberts, L. S. and Larson, A. ''Animal Diversity''. McGraw-Hill 2003 {{ISBN|0-07-234903-4}}</ref><ref name="Miller 2002">Miller, S. A. ''General Zoology Laboratory Manual'' McGraw-Hill, {{ISBN|0-07-252837-0}} and {{ISBN|0-07-243559-3}}</ref> For example, in [[horse]]s, the eyes are caudal to the nose and rostral to the back of the head.<ref name="Dyce2010"/>

In humans, "cranial" and "cephalic" are used to refer to the skull, with "cranial" being used more commonly. The term "rostral" is rarely used in human [[gross anatomy]] and refers more to the front of the face than the superior aspect of the organism. But it is used in [[Embryonic development|embryology]], and [[Anatomical terms of neuroanatomy|neuroanatomy]].  Similarly, the term "caudal" is used more in embryology and neuroanatomy, and only occasionally in human gross anatomy.<ref name="Gray's"/> The "rostrocaudal axis" refers to the curved line of the  [[neuraxis]] from the forehead (rostral) towards the tail end (caudal).

===Central and peripheral===
Central and peripheral refer to the distance towards and away from the centre of something. That might be an organ, a region in the body, or an anatomical structure. For example, the [[central nervous system]] and the [[peripheral nervous system]]s.

'''Central''' ({{ety|la|centralis}}) describes something at, or close to the centre.<ref>{{cite web |title=Definition of Central |url=https://www.merriam-webster.com/dictionary/central |website=www.merriam-webster.com |access-date=23 March 2025 |language=en |date=23 March 2025}}</ref>  For example, the [[great vessels]] run centrally through the body; many smaller vessels branch from these. 

'''Peripheral''' ({{ety|la|peripheria}}, originally from [[Ancient Greek]]) describes something that is situated nearer to the body's surface, such as a [[peripheral nerve]].<ref>{{cite web |title=Peripheral |url=https://www.collinsdictionary.com/dictionary/english/peripheral |access-date=23 March 2025}}</ref>

{{Anchor|superficial|deep}}

===Superficial and deep===
These terms refer to the distance of a structure from the surface.<ref name="Gray's"/><ref name="libre4">{{cite web |title=1.4B: Directional Terms |url=https://med.libretexts.org/Bookshelves/Anatomy_and_Physiology/Anatomy_and_Physiology_(Boundless)/1%3A_Introduction_to_Anatomy_and_Physiology/1.4%3A_Mapping_the_Body/1.4B%3A_Directional_Terms |website=Medicine LibreTexts |access-date=4 March 2025 |language=en |date=18 July 2018}}</ref>

'''Deep''' ({{ety|ang}}) describes something further away from the surface of the organism.<ref name="libre4"/> For example, the [[external oblique muscle]] of the abdomen is deep to the skin. "Deep" is one of the few anatomical terms of location derived from [[Old English]] rather than Latin – the anglicised Latin term would have been "profound" ({{ety|la|profundus|due to depth}}).<ref name="Dyce2010"/>

'''Superficial''' ({{ety|la|superficies|surface}}) describes something near the outer surface of the organism.<ref name="Dyce2010"/> For example, in [[skin]], the [[epidermis]] is superficial to the [[subcutis]].<ref name="libre4"/>

=== Combined terms ===
[[File:Posterior Parietal Lobe.jpg|thumb|[[Dorsolateral prefrontal cortex]] highlighted in dark green]]
Many anatomical terms can be combined, either to indicate a position in two axes simultaneously or to indicate the direction of a movement relative to the body. For example, '''anterolateral''' indicates a position that is both anterior and lateral to the body axis (such as the bulk of the [[pectoralis major]] muscle), or to a named organ such as the [[anterolateral tibial tubercle]].<ref name="Moore2018">{{cite book |last1=Moore |first1=Keith L. |last2=Dalley |first2=Arthur F. |last3=Agur |first3=Anne M. R. |title=Clinically oriented anatomy |date=2018 |publisher=Wolters Kluwer |location=Philadelphia Baltimore New York London Buenos Aires Hong Kong Sydney Tokyo |isbn=9781496347213 |page=679 |edition=Eighth}}</ref> The term can also describe the direction and location of something that enters or courses through the body such as the [[anterolateral system]] in the [[spinal cord]], and the [[anterolateral central arteries]].<ref>{{Cite web |title=Anatonomina |url=http://terminologia-anatomica.org/en/Terms/Occurence/4050 |access-date=2025-02-28 |website=terminologia-anatomica.org}}</ref>  Another term '''anteromedial''' is used for example in the [[anteromedial central arteries]].<ref>{{Cite web |title=Anatonomina |url=http://terminologia-anatomica.org/en/Terms/Occurence/4024 |access-date=2025-02-28 |website=terminologia-anatomica.org}}</ref>

In the more internal [[brain]] and [[spinal cord]] of the [[central nervous system]] the terms [[#Dorsal and ventral|dorsal and ventral]] and their combinations are often used in place of anterior and posterior. In these organs numerous references need to be used, and in the brain for example the [[prefrontal cortex]] has the divisions of the [[dorsomedial prefrontal cortex]], and the [[dorsolateral prefrontal cortex]].  And the dorsomedial region has subcompartments that make use of other terms such as the [[anterior cingulate cortex]], and [[infralimbic cortex]]. Structures such as the anterior cingulate cortex may be divided anatomically based on cognitive ([[Dorsum (biology)|dorsal]]), and emotional ([[ventral]]) components.<ref name="Bush00">{{cite journal | vauthors = Bush G, Luu P, Posner MI | title = Cognitive and emotional influences in anterior cingulate cortex | journal = Trends in Cognitive Sciences | volume = 4 | issue = 6 | pages = 215–222 | date = June 2000 | pmid = 10827444 | doi = 10.1016/S1364-6613(00)01483-2 | s2cid = 16451230 }}</ref>

'''Proximodistal''' is the axis of an [[appendage]] such as an arm or a leg, taken from its tip at the distal part to where it joins the body at the proximal part.<ref name="UNSW2025"/>

In [[radiology]], various [[Projectional radiography|X-ray views]] uses [[Projectional radiography terminology|terminology]]  based on where the X-ray beam enters and leaves the body, including the front to back view ('''anteroposterior'''), the back to front view ('''posteroanterior'''), and the side view ('''lateral''').<ref>{{cite book |last1=Hofer |first1=Matthias |title=The Chest X-ray: A Systematic Teaching Atlas |year=2006 |publisher=Thieme |isbn=978-3-13-144211-6 |page=24 |url=https://books.google.com/books?id=iERHEAWOk3oC&pg=PA24 |language=en}}</ref> Combined terms were once generally hyphenated, but typically the hyphen is omitted.<ref>{{cite dictionary |url=http://www.merriam-webster.com/dictionary/dorsolateral |title=dorsolateral |date=29 September 2023 |dictionary=Merriam-Webster}}</ref>

===Modifiers===
[[File:Radiate Oral-aboral Axes.JPG|thumb|Terms can be modified with prefixes and suffixes. In this image showing the [[jellyfish]] species ''[[Chrysaora]]'', the prefix 'ab-', is used to indicate something that is 'away from' the mouth, for example the '''aboral'''. Other terms are combined to indicate axes, such as proximodistal axis.]]

Several terms are commonly seen and used as [[prefix]]es:<ref name="Terms2025">{{cite web |title=medical terms |url=https://www.ucl.ac.uk/lapt/medterms.htm |website=www.ucl.ac.uk |access-date=9 March 2025}}</ref>

* '''Sub-''' ({{ety|la|sub|preposition beneath, close to, nearly etc}}) is used to indicate something that is beneath, or something that is subordinate to or lesser than.<ref name="Terms2025"/> For example, [[Subcutaneous tissue|subcutaneous]] means beneath the skin.
* '''Hypo-''' ({{ety|grc|ὑπό|under}}) is used to indicate something that is beneath.<ref name="Terms2025"/> For example, the [[hypoglossal nerve]] supplies the muscles beneath the tongue.
* '''Infra-''' ({{ety|la|infra|under}}) is used to indicate something that is within or below. For example, the [[infraorbital nerve]] runs within the [[orbit (anatomy)|orbit]].
* '''Inter-''' ({{ety|la|inter|between}}) is used to indicate something that is between.<ref name="Terms2025"/> For example, the [[intercostal muscle]]s run between the [[rib]]s.
* '''Super-'' or ''Supra-''' ({{ety|la|super, supra|above, on top of}}) is used to indicate something that is above something else.<ref name="Terms2025"/> For example, the [[supraorbital ridge]]s are above the [[eye]]s.
* '''Ab-''' ({{ety|la|ab|away}}), and '''ad-''' ({{ety|la|ad|towards}}) are used to indicate that something is towards (ad-) or away from (ab-) something else.<ref name="Terms2025"/> For example [[abduction and adduction]] refer to muscular movement away from, and towards the midline of the body, respectively.

Other terms are used as [[suffix]]es, added to the end of words:
* '''-al''' ({{ety|la|al|pertaining to, of the}}) For example [[femoral neck]].
* '''-ad''' ({{ety|la|ad|towards}}), equivalent to '-ally', is a suffix createing the adverb form to indicate that something moves towards (-ad) something else.<ref name= "GGHDHD">{{cite book |last1=Gordh |first1=Gordon |last2=Headrick |first2=David H |title=A Dictionary of Entomology |publisher=CABI |year=2011 |edition=2nd |isbn=978-1845935429|url=https://archive.org/details/dictionaryofento0000gord}}</ref> For example, "distad" means "in the distal direction,"<ref name="MW2025c">{{cite web |title=Medical Definition of Distad |url=https://www.merriam-webster.com/medical/distad |website=www.merriam-webster.com |access-date=15 March 2025 |language=en}}</ref> as in "arterial blood flows distad/distally." Further examples may include cephalad (towards the cephalic end), orad, craniad, and proximad. The terms "proximally" and "distally" are in more common use in human and veterinary anatomic textbooks, while "proximad" and "distad," are used commonly in insect anatomy.<ref name="Gray's"/><ref name="Dyce2010"/><ref name= "GGHDHD"/>