Fig. to keep resenting and disliking someone over a period of time. (Usually implies that it has been an unreasonably long time.) Sally is still nursing a grudge against Mary.How long can anyone nurse a grudge?
Bear resentment for a long time, as in We don't know why Karl looks so angry; I think he's nursing a grudge against the family. This expression uses nurse in the sense of "foster a feeling," a usage dating from the mid-1700s.