In mathematical finite group theory, the Thompson subgroup  of a finite p-group P refers to one of several characteristic subgroups of P.  originally defined  to be the subgroup generated by the abelian subgroups of P of maximal rank.
In finite group theory, a Thompson subgroup of a finite p-group P is defined as one of several characteristic subgroups of P.  Originally, it was characterized by being the subgroup generated by the abelian subgroups of P with maximal rank.