Apex (geometry)

In geometry, an apex (Latin for 'summit, peak, tip, top, extreme end;') is the vertex which is in some sense the highest of the figure to which it belongs.

• In an isosceles triangle, the apex is the vertex where the two sides of equal length meet, opposite the unequal third side.
• In a pyramid or cone, the apex is the vertex opposite the base.

References

• Weisstein, Eric W., "Apex", MathWorld.