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1. The point of intersection of lines or the point opposite the base of a figure
    
2. The highest point (of something)
   "at the vertex of the pyramid";
   - peak, apex, acme
    
3. The top of the head
   - pate, poll, crown

Derived forms: vertexes, vertices

Type of: extreme, extreme point, extremum, intersection, intersection point, point of intersection, top, top side, upper side, upside

Part of: human head

Encyclopedia: Vertex