a grudge
of a person, deploring someone or something
to bear one a grudge―owe one a grudge―have a grudge against one
to bear one a grudge―owe one a grudge―have a grudge against one
to revenge one's wrongs―revenge oneself―be revenged―pay off old scores―wipe off old scores―settle accounts with one―quit scores with one―get even with one―get square with one
the act of grumbling to oneself