One who doesn't currently have a proficient source of revenue and stable occupation.
One who often partakes in the benefits of the leisurely lifestyle. Often residing in his or her parental abode, he or she might even spend most of their day engaging in television and video game recreation. You might find him or her on said parent's couch.
Greg: Hey Gooch Nugget, where you at?
Ron: I'm at my parent's house.
Greg: Dude, when are you getting a job?
Ron: I've got a job, Queef Cookie, I'm a Professional Idler.
Ron: Mom! Moooom! Mooooooooom!
Ron: Use my Professional Idler income to buy some friggin pizza, I'm so hungry I could eat a hooker.