vertex

vertex — noun

1. In geometry, the place where two straight edges meet at a corner; for shapes wit

1.名詞B2
釋義

In geometry, the place where two straight edges meet at a corner; for shapes with a base, it is the tip located across from the bottom side.

例句

Each corner of a triangle is called a vertex in geometry class.

The two sides of the angle meet at a single vertex.

at + the + vertex + of + noun phrase

同義詞
  • corner

    everyday word; less formal than 'vertex'; used for rooms, boxes, streets, not for abstract geometric points

  • apex

    specifically the highest vertex opposite the base; overlaps only for triangles, pyramids, and cones

  • intersection

    where lines cross each other, not just meet; reserved for crossing rather than corner-forming junctions

文法句型

vertex + of + noun phrase

at + the + vertex + of + noun phrase

plural form: vertices

用法筆記

The standard plural form in mathematics is 'vertices', though 'vertexes' is also accepted. This is the only sense that takes a plural count reading — you can refer to 'the vertices of a polygon' but not 'the vertices of a mountain'.

常見錯誤

❌The vertex of a circle is at its centre.
✅A circle has no vertex because it has no straight edges or corners.
💡A vertex is defined only where straight lines meet, and a circle has no straight edges.
❌Each corner of the room is a vertex.
✅Each corner of the room can be thought of as a vertex.
💡In everyday contexts, 'corner' is preferred; 'vertex' is used in formal geometry contexts.

2. The highest or topmost point of a physical object, such as a mountain, arch, dom

2.名詞C1
釋義

The highest or topmost point of a physical object, such as a mountain, arch, dome, or ridge.

例句

The vertex of the arch stood fifteen metres above the road.

vertex + of + physical object

Kabir took a photo from the vertex of the hill at sunrise.

同義詞
  • summit

    more common for mountains; suggests a successful climb or achievement

  • apex

    interchangeable with 'vertex' in this sense; 'apex' is slightly more common for arches and curves

  • peak

    most common everyday word; used for mountains, roofs, and performance (reaching a peak)

反義詞
  • base

    the lowest supporting part of an object

  • bottom

    the lowest point of something

文法句型

vertex + of + noun phrase

at + the + vertex + of + noun phrase

用法筆記

More formal than 'top' or 'summit'. Preferred in descriptions of architecture, sculpture, or landscape. Unlike sense 1, this sense is almost always singular and is never used in the plural to describe multiple objects.