What is malherb?

Some articles on malherb:

The American Prisoner
... The heroine's father, Maurice Malherb, is based on Thomas Windeatt ... In the novel Malherb is a miscreant who destroys Childe's tomb and beats his servant ... Malherb is introduced as the younger son of a noble family and he builds the Fox Tor house to be the impressive gentleman's residence suggested by William Crossing rather than the humble cottage ...