Book royalties refer to the money that authors receive as a percentage of the sales of their published book. It is a form of payment for using their intellectual work and ideas in the book. Full definition
My co-authors are considered contractors and therefore have received a portion of book royalties in the past. (worderella.com)
He makes a living from book royalties and fees from speaking for hire. (scottberkun.com)
That's important to understand because, quite honestly, it's unlikely that you'll earn back your publicist fees in book royalties or sales alone. (buildbookbuzz.com)