The Collaborative International Dictionary of English v.0.48:

Professorial \Pro`fes*so"ri*al\, a. [L. professorius: cf. F.
   professorial.]
   Of or pertaining to a professor; as, the professional chair;
   professional interest.
   [1913 Webster]

WordNet (r) 3.0 (2006):

professorial
    adj 1: relating to or characteristic of professors;
           "professorial demeanor"

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "professorial":
   academic, bookish, devoted to studies, diligent, donnish,
   dryasdust, mandarin, owlish, pedagogic, pedantic, preceptorial,
   professorlike, rabbinic, scholarly, scholastic, schoolmastering,
   schoolmasterish, schoolmasterlike, schoolmasterly, schoolmistressy,
   schoolteacherish, schoolteachery, studious, teacherish,
   teacherlike, teachery, teachy, tutorial