An actor or actress—a person who performs roles in theater, film, etc. (common, sometimes colloquial).
彼は舞台で長年活躍している役者だ。
He is an actor who has been active on stage for many years.
その映画には有名な役者が出演している。
Famous actors appear in that movie.
若い役者たちがオーディションを受けている。
Young actors are auditioning.
彼女はプロの役者として生活している。
She makes her living as a professional actor.
A clever or cunning person—used colloquially to describe someone who is crafty, witty, or puts on an act.
あの人は本当に役者だ、話を聞くと何でもうまく切り抜ける。
That person is really a crafty one; he manages to get out of anything when you talk to him.
交渉では彼が役者ぶりを発揮した。
He displayed his skillful (actor-like) manner during the negotiations.