The House of Mirth
by Edith Wharton
Book Two: chapters XIII, XIV

What is the word?
In the last minutes before Lily "slept," she was vaguely reminded of a word she needed to tell Selden. However, the chloral took over and she was not able to remember fully: "slowly the thought of the word faded." When I first read about the word, I immediatly thought of the word love. Lily wanted to tell Selden she loved him. Then, after reading that Selden also had a word he wanted to tell Lily, my initial thought was strengthened. Selden's actions and thoughts added to my hunch that the word was love. Even Gerty's insistence that Lily would have wanted Selden to go through her things supported the idea.
I think Wharton purposfully omitted the word to leave the reader wondering what Lily felt before she died and to make a connection between Lily and Selden's thoughts toward each other. Because both Selden and Lily had a word they wanted to tell each other, I got a sense that they had both come to the same realization that they loved each other.