There's now one word Caitlyn Jenner has banned from her life, and it speaks volumes.

According to Kim Kardashian West, there’s one word 67-year-old Caitlyn Jenner has barred from her life.

“She doesn’t like to say that word,” the 36-year-old told talk show host Ellen Degeneres on Thursday, referring to her family’s infamous surname.

Speaking about the now fraught relationship between Caitlyn, her ex-wife Kris Jenner, the two daughters they share (Kendall and Kylie Jenner) and the four Kardashian children they co-raised together (Kourtney, Kim, Khloe and Robert Kardashian) Kardashian West said, "For the Kardashians," using air quotes around her surname, "she [Caitlyn] doesn't like to say that word... she said that in her book."

Then, referring to Caitlyn's "coming out interview" in 2015, Kim added, "on Diane Sawyer, she purposely never said our name."

Since being released this week, Caitlyn's memoir The Secrets of My Life has caused a major rift between the famous family, with Kris Jenner and a number of the Kardashian children now cutting off contact with the woman who raised them for much of their lives.

Among other major topics, the book discusses details about Caitlyn and Kris' 24-year-long marriage and intimate information about their sex life.

"I think it's unfair," Kardashian West told DeGeneres. "Things [written about Kris Jenner] aren't truthful...it's just so hurtful."

The mum-of-two added, "I wish her all the success in the world but not at our expense."

When DeGeneres asked if Kardashian West still has a relationship with Caitlyn, Kim responded, "I haven't talked to her in a couple of weeks. I'll always love her, that was my stepdad for so many years. She taught me about character and so much growing up, and I just feel like I don't respect the character that she's showing now."

She added finally, "There's no need for a book. Tell your story but just don't bash other people. I just think it's not tasteful."