constitutionalist noun 2adjective 1forms 3 noun2 •A person who adheres to the philosophy of constitutionalism.It was now getting late, and Mr. Morland summoned them to depart; for he was a constitutionalist in the best sense of the word. It was his own constitution to which he attended. — 1831 •A person who is expert in constitutional law. adjective1 •Of or relating to constitutionalism or its adherents. formsconstitutionalists · more constitutionalist · most constitutionalist