When an illustration/comics job listing says "pros only" what does this...mean? Like. What do they consider pro to mean? I'm technically published, but only online, and self published in print. I do art full time but I don't have a degree. What does pro mean to you?

I think my overall thought is...if you think you'd be good at a job, and it sounds right for you, but it says "pros only" don't be discouraged! Apply anyway. Who knows what'll happen lmao