This phrase is worth noting precisely because it does not belong in this
dictionary: it makes sense in a moral universe that has utterly vanished. The last "
cad and bounder" died, perhaps, about 1947 (see London Daily Telegraph obituaries for further evidence).
Although they are appropriately linked, the precise meanings differ. A "cad" is one who does harm to a
woman's honor or sense of self-worth as, for example, by taking her for a garden
walk when he has no intention of marrying her. A "bounder" is a presumptious upstart, seemingly ignorant of, but perhaps merely indifferent to, fundamental norms of propriety.