A ProfessionalStudent is someone who appears to be making a career of post-graduate education, by remaining in doctoral program(s) long after all of his/her colleagues have matriculated, left for the RealWorld, or died.
Or perhaps one, like myself, who considers that Education Is LifeLongLearning and continues taking courses even after receiving degrees. -- DonaldNoyes.200809181859.m06
You'd be an EternalStudent. Big difference.