In To Kill A Mockingbird, Uncle Jack relates a story about Lord Melbourne to Scout. In history, Lord Melbourne was Queen Victoria's first Prime Minister. Melbourne had the reputation for being something of a ladies' man.
This is the story Uncle Jack tries to share with Scout when Scout asked him what was a whore-lady? Uncle Jack is caught by surprise at Scout's question. He tries to share a story about a character who is morally in question. Scout says Uncle Jack's story made no sense:
Uncle Jack plunged into another long tale about an old Prime Minister who sat in the House of Commons and blew feathers in the air and tried to keep them there
when all about him men were losing their heads. I guess he was trying to answer my question, but he made no sense whatsoever.
No doubt, Uncle Jack is caught off guard when Scout asks the following question:
'What’s a whore-lady?'
Uncle Jack does not come right out and answer Scout's question. For this reason, Atticus tells him that he should be more direct:
Jack! When a child asks you something, answer him, for goodness' sake. But don't make a production of it. Children are children, but they can spot an evasion quicker than adults, and evasion simply muddles 'em.
Clearly, Scout's direct questions can be challenging. It is not surprising that Uncle Jack did not know exactly how to answer Scout's "whore-lady" question. While he was trying to answer her question, Scout said "he made no sense whatsoever."