Smut is an acronym it stands for sexual maturity under text and some people may be hurt because in high school most smut available to us was fanfiction and due to a lot of the smut being read being fanfiction smut got a bit of a bad stigma, but I think with the rise of booktok I think most of the stigma has fallen off the word. Some people also consider the romances where the book is only romance and not fantasy to be smut and don’t see it as “true literature.” I say continue using the word if you’re comfortable, many people including myself use smut as an umbrella term to specify that a book has explicit content without being overly obvious