MAOI en · NOUN Meanings (abbreviation, alt-of, initialism) Initialism of monoamine oxidase inhibitor. alt of monoamine oxidase inhibitor ‘Sertraline in combination with an MAOI will kill you, in enough quantities.’ 1996, David Foster Wallace, Infinite Jest […], Boston, Mass.; New York, N.Y.: Little, Brown and Company, →ISBN, page 70: Forms SpellingFeaturesLabelsSource MAOIs Number=Plur lexicographic Relateds MAO