'co-author' definitions:

Definition of 'co-author'

(from WordNet)
verb
Be a co-author on (a book, a paper)

Definition of 'co-author'

From: GCIDE
  • co-author \co-author\ v. t.
  • 1. to to be an author of, together with another author or authors; to author jointly with others. [WordNet 1.5]
  • 2. to exist together at the same time.
  • Syn: coexist. [WordNet 1.5]