noun the top, or crown, of the head.
2. vertex ·noun the zenith, or the point of the heavens directly overhead.
3. vertex ·noun a turning point; the principal or highest point; top; summit; crown; apex.
4. vertex ·noun the point in any figure opposite to, and farthest from, the base; the terminating point of some particular line or lines in a figure or a curve; the top, or the point opposite the base.