What is another word for writer of author?

There isn't really a single perfect synonym for "writer" when referring to someone who writes books. Here are some options depending on the context:

Formal:

* Author (this is the most common and formal term)

* Novelist (if they write novels)

* Playwright (if they write plays)

* Poet (if they write poetry)

* Screenwriter (if they write for film or TV)

* Librettist (if they write opera librettos)

* Essayist (if they write essays)

* Historian (if they write historical accounts)

Informal:

* Scribbler (this can be slightly derogatory)

* Wordsmith (a more positive, poetic term)

* Storyteller (emphasizes the creative aspect)

* Penman/Penwoman (an older term)

The best option really depends on the specific context and the tone you want to convey.