vertex

American  

[vur-teks] / ˈvɜr tɛks /

noun

plural

vertexes, vertices

1. the highest point of something; apex; summit; top.

   the vertex of a mountain.

2. Anatomy, Zoology. the crown or top of the head.

3. Craniometry. the highest point on the midsagittal plane of the skull or head viewed from the left side when the skull or head is in the Frankfurt horizontal.

4. Astronomy. a point in the celestial sphere toward which or from which the common motion of a group of stars is directed.

5. Geometry.

   1. the point farthest from the base.

      the vertex of a cone or of a pyramid.

   2. a point in a geometrical solid common to three or more sides.

   3. the intersection of two sides of a plane figure.

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vertex British  

/ ˈvɜːtɛks /

noun

1. the highest point

2. maths

   1. the point opposite the base of a figure

   2. the point of intersection of two sides of a plane figure or angle

   3. the point of intersection of a pencil of lines or three or more planes of a solid figure

3. astronomy a point in the sky towards which a star stream appears to move

4. anatomy the crown of the head

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vertex Scientific  

/ vûr′tĕks′ /

plural

vertices

1. The point at which the sides of an angle intersect.

2. The point of a triangle, cone, or pyramid that is opposite to and farthest away from its base.

3. A point of a polyhedron at which three or more of the edges intersect.

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Etymology

Origin of vertex

First recorded in 1560–70; from Latin: “a whirl, top (of the head),” equivalent to vert(ere) “to turn” + -ex (stem -ic- ) noun suffix

Explanation

If you’ve reached the vertex of something, you know it’s all downhill after that, because vertex refers to the highest point on an object, such as the top of a mountain. In its early usage vertex referred to the top of a person’s head. That meaning is still common, especially in the field of anatomy, but these days you can use the word in a broader sense to refer to the highest point of anything. Still, it’ll help you remember the meaning of vertex if you visualize the top of someone’s head — the highest point — when you think of this word. If you want to get technical, in the field of mathematics, vertex can refer to the point at which lines meet and form an angle, or to the point on a figure, such as a triangle or cone, that is opposite to its base.

Example Sentences

This was practically confirmed using a vertex cover problem with 4096 vertices.

From Science Daily • Mar. 25, 2024

A nonlinear system could be representative of a parabola and a circle, where the vertex of the parabola meets the circle and the branches also intersect the circle, hence three solutions.

From Textbooks • Dec. 21, 2021

The vertex of the graph of the quadratic function in the form .

From Textbooks • Sep. 23, 2020

Be sure to label the vertex as an ordered pair.

From Textbooks • Sep. 23, 2020

I stared at the peak for perhaps thirty minutes, trying to apprehend what it would be like to be standing on that gale- swept vertex.

From "Into Thin Air" by Jon Krakauer