1. Happening or being casual; unimportant, not remarkably significant: "Mr. Thorpe was an outstanding lawyer, and incidentally, he was also a singer, performing with the local operetta society."

"The government report discussed the spying problem only incidentally."

2. Conveying an introduction or a statement which provides added information or includes another topic: "Oliver recently met his friend's wife, who incidentally is a well-known reporter on TV."

"Incidentally, Corinne saw Rebecca today and she recently got a job with a publisher as an editor."