voice acting; appearing as a voice actor
Used in credits for films, TV shows, games, etc. to indicate that a person performed as a voice actor. Often seen in the form 「声の出演：名前」.
See also: 出演
In this animated film, a famous actor makes a voice appearance.
エンドロールに「声の出演」として彼の名前があった。
His name was in the end credits under 'voice cast'.
Compound of 声 (voice) + の (possessive particle) + 出演 (appearance).