A person who loves or vehemently propounds his or her own opinions; a dogmatic or argumentative person.
Chiefly in translations of Montaigne..
Origin
Early 17th century; earliest use found in John Florio (1553–1625), author and teacher of languages. From French philodoxe and its etymon ancient Greek ϕιλόδοξος loving belief or opinion (Plato) from ϕιλο- + δόξα opinion, glory.