Lady Catherine is shocked that her nephew will marry a woman whose uncle is an attorney, while we are presented Darcy's great-uncle the judge as yet another sign of his family's prestige. This post isn't going to go into the importance of judges, but I am going to talk about the great uncle's probably previous profession - that of barrister.
The differences are primarily that barristers were trial lawyers who plead cases in court while attorneys were agents who transacted business on behalf of their clients (the types of things that a transactional lawyer might do).
Barristers were more prestigious because they typically had university educations, better connections and were not in trade because they didn't (and in fact couldn't) take fees directly from their clients while attorneys were considered to be in trade and did take fees, both their own and the fees that they would then give to the barrister if the situation at hand called for one.
Labels: History, Law, Social Rank