doctrinaire UK /ˌdɒk.tɹɪˈnɛə̯/US /ˌdɑk.tɹɪˈnɛɹ/noun 2adjective 1forms 3 noun2 •A person who stubbornly holds to a philosophy or opinion regardless of its feasibility.Or, shall we play the doctrinaire, and hint that at thirty-four the tides of life are calmer and cognizant of many sources instead of but one—as at four-and-twenty? — 1909 •(historical) In France, in 1815–30, a faction that advocated a constitution modeled on that of Britain. adjective1 •Stubbornly holding on to an idea without concern for practicalities or reality.We have been long accustomed to consider growth as applied almost exclusively to size in its various aspects. But Nature, who has no doctrinaire ideas, may equally apply it to concentration. — 1911 formsdoctrinaires · more doctrinaire · most doctrinaire