The graph tensor product, also called the graph cardinal product (Imrich 1998), graph categorical product, graph conjunction, graph direct product (Hammack et al. 2016),
graph Kronecker product (Weichsel 1962), graph relational product, or graph weak
direct product, is the graph product denoted 
and defined by the adjacency
relations (
and 
).
Letting 
denote the adjacency matrix, the graph tensor
product of simple graphs 
and 
is given by
 |
where 
denotes the Kronecker product (Hammack et
al. 2016).
The graph tensor product 
is known as the bipartite
double graph of 
.
