# vertex

noun ver·tex \ ˈvər-ˌteks \
Updated on: 8 Jan 2018

## Definition of vertex

plural vertices\ˈvər-tə-ˌsēz\ 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

## Recent Examples of vertex from the Web

• Existing small drones are usually polycopters—helicopters that have a set of rotors (generally four or six) arranged at the vertices of a regular polygon, rather than a single one above their centre of gravity.
• And a narrowing of the cerebrospinal fluid spaces at the vertex, the top of the skull, was apparent in 12 long-term astronauts but only one of the short-term astronauts.
• In graph theory, however, the points are called vertices and the lines are called edges.
• Since the cone has its vertex at the origin, the radius of each horizontal slice will be the x value of that function.

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'vertex.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

## Origin and Etymology of vertex

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

noun

## Definition of vertex for English Language Learners

• : a point where two lines meet to form an angle; especially : the point on a triangle that is opposite to the base

## vertex

noun ver·tex \ ˈvər-ˌteks \

## Definition of vertex for Students

plural vertices \ˈvər-tə-ˌsēz\ also vertexes
1 : the point opposite to and farthest from the base of a geometrical figure
2 : the common endpoint of the sides of an angle

## vertex

noun ver·tex \ ˈvər-ˌteks \

## medical Definition of vertex

plural vertices\ˈvərt-ə-ˌsēz\ also vertexes
1 : the top of the head
2 : the highest point of the skull

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