# vertex
## English
### Etymology

Late Middle English, borrowed from Latin vertex (“whirl, eddy; top, crown, peak, summit”). Doublet of vortex.

### Pronunciation

* (Received Pronunciation) IPA: /ˈvɜː.tɛks/
* (General American) IPA: /ˈvɝˌtɛks/
* Audio (US):(file)
* Rhymes: -ɜː(ɹ)tɛks

### Noun

vertex (plural vertices or vertexes)
* The highest point, top or apex of something.
    Synonyms: acme, apex, peak, top
    Antonym: fundus
** (anatomy) The highest surface on the skull; the crown of the head.
* (geometry) An angular point of a polygon, polyhedron or higher order polytope.
** The common point of the two rays that form an angle.
** The point at which an axis meets a curve or surface.
* (mathematics) A point on the curve with a local minimum or maximum of curvature.
* (graph theory) One of the elements of a graph joined or not by edges to other vertices.
    Synonym: node
    Coordinate term: plot
* (computer graphics) A point in 3D space, usually given in terms of its Cartesian coordinates.
* (optics) The point where the surface of a lens crosses the optical axis.
* (particle physics) An interaction point.
* (astrology) The point where the prime vertical meets the ecliptic in the western hemisphere of a natal chart.
* (typography) A sharp downward point opposite a crotch, as in the letters "V" and "W" but not "Y".
    Coordinate term: apex

#### Derived terms

* antivertex
* covertex
* frontovertex
* hypervertex
* intervertex
* intravertex
* nonvertex
* supervertex
* vertexal, vertexial
* vertex angle
* vertex cover
* vertex figure
* vertex form
* vertexless
* vertex separation number
* vertexwise

#### Related terms

* vertical

#### Translations

    The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

### See also

* Mathworld article on vertices of polyhedra
* Mathworld article on vertices of polygons

### References

* “vertex”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.
* “vertex”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.

## French
### Etymology

Borrowed from Latin vertex.

### Pronunciation

* IPA: /vɛʁ.tɛks/
* Audio:(file)

### Noun

vertex m (plural vertex)
* (anatomy) vertex

### Further reading

* “vertex” in Émile Littré, Dictionnaire de la langue française, 1872–1877.
* “vertex”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.

## Latin
### Alternative forms

* vortex (archaic)

### Etymology

From vertō (“to turn around, turn about”).
(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.)

### Pronunciation

* (Classical Latin) IPA: /ˈu̯er.teks/, [ˈu̯ɛrt̪ɛks̠]
* (modern Italianate Ecclesiastical) IPA: /ˈver.teks/, [ˈvɛrt̪eks]

### Noun

vertex m (genitive verticis); third declension
* whirl, whirlpool, eddy, vortex
* eddy of wind or flame, whirlwind, coil of flame
* (literally, anatomy) top, crown of the head
* (poetic) head
    vacuus vertex ― an empty head
* pole of the heavens (north or south)
* highest point, top, peak, summit (of a mountain, house, tree, etc.)
    Synonyms: cacūmen, apex, culmen, fastīgium, summitās
    Antonym: fundus
    a vertice ― from above/at the top
    in verticem ― upright/vertically
* (figurative, poetic) highest, uttermost, greatest

#### Inflection

Third-declension noun.

#### Derived terms

* bivertex
* quinquevertex
* verticillus
* verticōsus
* verticula

#### Descendants

* Lombard: vierdza, verdza, értes, vértisa (“parting of the hair”)
* Piedmontese: verdz̆a (“peak”)
* Romansch: viertsch, vertscha
Early borrowings:
* → Old French: vertiz (“top of the head”)
* → Old Occitan: vertitz, vertis
Later borrowings:
* → English: vertex
* → French: vertex
* → Italian: vertice
* → Portuguese: vértice
* → Sicilian: vèrtici
* → Spanish: vértice

### References

* “vertex”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
* “vertex”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
* "vertex", in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
* vertex in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
* Carl Meißner, Henry William Auden (1894) Latin Phrase-Book‎, London: Macmillan and Co. the pole: vertex caeli, axis caeli, cardo caeli
* Dizionario Latino, Olivetti
* Walther von Wartburg (1928–2002) “vĕrtex”, in Französisches Etymologisches Wörterbuch, volumes 14: U–Z, page 320
* Meyer-Lübke, Wilhelm (1911) “vĕrtex”, in Romanisches etymologisches Wörterbuch (in German), page 706

## Romanian
### Etymology

Borrowed from French vertex, from Latin vertex.

### Pronunciation

* IPA: /ˈver.teks/

### Noun

vertex n (uncountable)
* vertex

#### Declension
### Further reading

* vertex in DEX online—Dicționare ale limbii române (Dictionaries of the Romanian language)