A tetrahedron in a graph is a tetrahedral graph subgraph, i.e., a 
-subgraph.
A graph with no 
-subgraphs
may be termed a tetrahedron-free graph.
Graph Tetrahedron
See also
Graph Cycle, Graph Triangle, Subgraph, Tetrahedral Graph, Tetrahedron, Tetrahedron-Free GraphExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Graph Tetrahedron." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/GraphTetrahedron.html