VertexLabelStyle is an option and property for Graph and related functions that specifies the style to use for vertex labels.
VertexList[g] gives the list of vertices for the graph g.VertexList[g, patt] gives a list of vertices that match the pattern patt.
VertexNormals is an option for graphics primitives which specifies the normal directions to assign to 3D vertices.
VertexOutComponent[g, {v_1, v_2, ...}] gives the vertices in the graph g that have a directed path from at least one of v_1, v_2, ....VertexOutComponent[g, {v_1, v_2, ...}, ...
VertexRenderingFunction is an option for GraphPlot and related functions that gives a function to generate the graphics primitives to use in rendering each vertex.
VertexReplace[g, {v_1 -> w_1, v_2 -> w_2, ...}] replaces each vertex v_i in the graph g by w_i.
VertexShapeFunction is an option and property for Graph and related functions that specifies a function to use to generate primitives for rendering each vertex.
VertexSize is an option and property for Graph and related functions that specifies the size used for vertices.
VertexTextureCoordinates is an option for graphics primitives that specifies the texture coordinates to assign to vertices.
VertexWeight is an option and property for Graph and related functions that specifies a vertex weight.