The Writer's Voice: What Is It Really?
The best explanation I've found is in the wonderful book Manuscript Makeover: Revision Techniques No Fiction Writer Can Ignore. In it, author and writing teacher Elizabeth Lyon explains what many editors and agents find difficult to describe, since the words "style" and "voice" are often used to describe an author's writing.
A quote from Lyons:
"Style is based on "wordsmithing", choosing and tweaking words to create the desired effect and to fit a character and genre. Voice is the author's natural use of language to create authentic and original characters and unique storytelling. More simply stated, style is the outcome of voice, more so than vice versa."
Lyons gives several examples where different styles of writing about the same object sound vastly different. Picture an old rusted car. Now imagine three writers describing the same car. One writer is an inner-city gang member, another is a wealthy Englishman, and a third writer is you.
Will the specific vocabulary vary in the three descriptions? Quite a bit. Each voice will have a distinction of its own. (This is one reason writers rarely need to worry about someone "stealing" their idea. Even if someone nabbed a copy of your novel outline, your voice is what makes your story completely unique.)
I've collected a few good articles that will shed more light on the voice issue:
Agent Nathan Bransford explains How to Craft a Great Voice. (For more on Bransford, click here.)
Agent Rachelle Gardner tells what voice isn't, and what it is in The Writer's Voice, and she shares the difference between Craft, Story and Voice. (for more on Gardner, click here.)
Musician Heather Goodman gives three exercises for writers to use in finding their voice in A Musician Looks at Writing.
And lastly, amazing 16-year-old writer Tessa shows she's wise beyond her years with her prescription in Have You Lost Your Writing Voice? Excellent advice.