Prostitute. If there's one thing I hate, it's the movies. Don't even mention them to me.
Holden is literally accusing his brother of selling out and exploiting his writing just because he now works for the movies. His extreme comparison of DB to a “prostitute” should come as a surprise to you.
To help improve the meaning of these lyrics, visit "The Catcher in the Rye (Chap. 1)" by J.D. Salinger and leave a comment on the lyrics box