I think the word hypocrisy most clearly stands out to Maudie in this chapter. Here these women are supposed to be together in the name of service to this missionary, J. Grimes Everett who is serving a poor group of people overseas (likely black ones). But, all they are doing is whining about local blacks they could be personally serving themselves. They celebrate what the missionary has done, and likely take up a collection to help him. If they are the Christian women they say that they are, they would be the hands and feet of Jesus so-to-speak to those who need service right in front of them, their Negro servants.
The announcement of Tom's death was an ultimate climax for this chapter as she had just spent time being hurt by what they say.
Furthermore, Maudie deeply cares for Atticus. She is tired of him being the savior of this town morally. She wishes someone would join him in his plight to do right by all people, not just those with the right color of skin.