coauthor removed other author's name after reviews
It may or may not technically be plagiarism, but it’s definitely fraud if it was done without your consent. Papers and book chapters can be retracted for such infractions.

If this has indeed happened, then your next step—assuming you've reached an impasse with your co-authors—should be to contact the editor and publisher of the book, laying out your case with the appropriate documentary evidence included in its entirety. Make sure they have enough information that they’re not going on a “fishing expedition.” There should be clear correspondence—emails showing the work and production of the article with your participation, and so on.