/
ˈvəːtɛks/
n.
 (pl. vertices  
/-tɪsiːz/
 or vertexes)
   - the highest point; the top or apex.
 - Geometry  each angular point of a polygon, polyhedron, or other figure. 
▸a meeting point of two lines that form an angle.
 - Anatomy  the crown of the head.
 
Etymology
ME: from L., ‘whirlpool, crown of a head, vertex’, from vertere ‘to turn’.