# vertex

## noun

ver·​tex
plural vertices also vertexes
1
: the top of the head
2
a
: the point opposite to and farthest from the base in a figure
b
: a point (as of an angle, polygon, polyhedron, graph, or network) that terminates a line or curve or comprises the intersection of two or more lines or curves
c
: a point where an axis of an ellipse, parabola, or hyperbola intersects the curve itself
3
: a principal or highest point : summit
the vertex of the hill

## Examples of vertex in a Sentence

Recent Examples on the Web The presenting part, which is the part of the baby's body that is born first in a vaginal delivery, is usually the baby's head (known as vertex presentation). Donna Murray, Rn, Parents, 25 July 2024 Their challenge was to extract an independent set using a large portion of vertices in the original graph. Quanta Magazine, 30 Apr. 2024 To find a periodic trajectory in an acute triangle, draw a perpendicular line from each vertex to the opposite side, as seen to the left, below. Quanta Magazine, 15 Feb. 2024 For example, Pythagorean triples (such as 3, 4 and 5), represent right triangles whose three vertices are all integer distances apart. Quanta Magazine, 1 Apr. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'vertex.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

## Word History

Etymology

Middle English, top of the head, from Latin vertic-, vertex, vortic-, vortex whirl, whirlpool, top of the head, summit, from vertere to turn

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of vertex was in the 14th century

vertex

## Cite this Entry

“Vertex.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/vertex. Accessed 5 Aug. 2024.

## Kids Definition

vertex

noun
ver·​tex
plural vertices also vertexes
1
: the point of a figure that is opposite to and farthest from its base
the vertex of a triangle
2
: the point where the two sides of an angle meet or where three or more edges of a polyhedron (as a cube) meet

## Medical Definition

vertex

noun
ver·​tex
plural vertices also vertexes
1
: the top of the head
2
: the highest point of the skull

## More from Merriam-Webster on vertex

Last Updated: - Updated example sentences
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