A 3D shape with one vertex is called a cone. It has a circular base and a single apex (the vertex) where all the lines from the base converge. The shape tapers smoothly from the base to the vertex, creating a pointed top. Other examples of shapes with one vertex include certain types of pyramids, but cones are the most common reference for this characteristic.
a coneA cone.
Cone
cone
triangle * * * * * A triangle is NOT a 3d shape! A cube.
A cone
CONE
Any polyhedron.
cone
A cone.
is it a vertex
a coneA cone.
Cone
The question is not particularly clear but I suspect that the answer is a vertex.
None
cone
triangle * * * * * A triangle is NOT a 3d shape! A cube.
a cone