"Miserly" means something that corresponds to or is associated with the behavior of a miser, which is someone who hoards, conserves or is otherwise unwilling to part with their possessions, particularly money. Miserly behavior can be thought of as the opposite of generosity, and might also be described as stingy. A miser hoards for the sake of hoarding, sometimes to the point of denying themselves and others very basic things in order to avoid the cost. Ebenezer Scrooge, from Charles Dickens' "A Christmas Carol", is a famous example of a miserly character, who controls every aspect of his business down to the number of lumps of coal used in the fire because he doesn't want to spend any more than necessary.
Tom (and his wife) are described outright as miserly, although we don't really see many particular examples of miserliness other than their constant squabbling over every possession in the household. Tom also was at least equally if not more concerned about the lost silverware than his wife's disappearance. However, what may be the best example of this behavior is Tom's unwillingness to furnish his new home, or even feed his horses, seeing as he has no practical need to do these things and only bought them in the first place for the sake of showing off. Tom might also be considered miserly because he devoted the entirety of his fortune not only to himself, but to hurting others through his business; none of his works were charitable.