A jestbook is typically defined as a book containing jokes or humorous anecdotes. However, there are a few other synonyms that can be used interchangeably with this term. One synonym is "joke book" which carries the same connotation of a book full of humorous content. Another synonym is "comic book", although this term is more often associated with graphic novels and comics centered around superheroes. A third synonym is "humor book", which is a broader term that encompasses any book that contains funny or amusing content. Whatever the term, these books are designed to make their readers chuckle and lighten their mood.