In geometry:
* The highest point of something: This is the most common meaning. For example, the vertex of a triangle is the point where two sides meet, the vertex of a cone is the point at the top, and the vertex of a parabola is the highest or lowest point on the curve.
* A point where lines or curves intersect: This meaning is also common in geometry, particularly when discussing angles. For example, the vertex of an angle is the point where the two rays that form the angle meet.
In other contexts:
* The highest point of a mountain or hill: This meaning is similar to the geometric meaning of "vertex."
* The point of greatest intensity: This meaning is often used figuratively to describe a moment of intense emotion or activity. For example, "The storm reached its vertex at 3:00 AM."
The specific meaning of "vertex" will depend on the context in which it is used.