How we cite our quotes: (Chapter.Paragraph)
Quote #1
The persons of their world lived in an atmosphere of faint implications and pale delicacies, and the fact that he and she understood each other without a word seemed to the young man to bring them nearer than any explanation would have done. (2.23)
Archer's duty to protect his fiancé's family's good name is implicitly understood by everyone. They don't even have to talk about it; they just know.
Quote #2
In the course of the next day the first of the usual betrothal visits were exchanged. The New York ritual was precise and inflexible in such matters […] (4.1)
Archer and May undergo a series of visits following their engagement. Such visits emphasize how much a part of New York society they are.
Quote #3
"I hear she means to get a divorce," said Janey blindly.
"I hope she will!" Archer exclaimed.
The word had fallen like a bombshell in the pure and tranquil atmosphere of the Archer dining room. (5.49-51)
Marriage is a duty that is unquestioned in New York society, so the word "divorce" has about the same effect as uttering an obscenity. Maybe they called it the 'd-word.'