Vertex
The vertex is the point where the ecliptic meets the prime vertical in the west, a calculated angle some astrologers read as a place of encounter.
It is a genuine geometrical point rather than a body, computed like the Ascendant and the Midheaven from the birth time and place, and like them it moves quickly enough that an inaccurate time destroys it.
Its interpretation is a modern addition and not part of the classical vocabulary: the reading of the vertex as a point of fated meetings dates from the twentieth century. Our written interpretations do not use it, and it appears here because readers meet the word.
Frequently asked
Is the vertex a classical point?
No. It is a twentieth-century addition, and we label it as one rather than presenting it as traditional doctrine.
Does it need an exact birth time?
Yes, as much as the Ascendant does. It is derived from the same inputs and moves at a comparable speed.