This document features just over 240 possible vocabulary words for Paul Kalanithi's When Breath Becomes Air. Twenty-one words that appear multiple times are noted as well. THIS PRODUCT IS JUST A LIST OF WORDS. The words are divided by the forward, prologue, Part I, Part II, epilogue, and acknowledgements. The Word document is editable.
You could ask students to highlight the words they don't know and build a class-determined vocabulary list from their responses. This is a great way to differentiate instruction.
If the book is a summer or independent read, the list could be an assignment where students define a specific number of words using the context of how/where the words appear in the book.