Definition of a seiyuu (I swear, this is really the last time I post in this thread and types like it):

http://www.animenewsnetwork.co...edia/lexicon.php?id=75

Short version for dial-uppers: Voice actor

The Lexicon at ANN is fairly complete and one can learn a great deal off it. Browse if you're new to anime/manga. I learned a lot from the manga related definitions myself.