Justinianist|dʒʌˈstɪnɪənɪst| [f. as prec. + -ist.] One who is learned in the Institutes of Justinian; a student of the civil law, a ‘civilian’. 1658Phillips, Students of the Civil Law are called Justinianists.1848Wharton Law Lex., Justinianist, a civilian; one who studies the civil law.