If you describe something as maddening, you mean that it makes you feel angry, irritated, or frustrated. Shopping in the January sales can be maddening = infuriating + maddeningly mad·den·ing·ly The service is maddeningly slow. very annoying = infuriating
extremely annoying or displeasing; "his cavelier curtness of manner was exasperating"; "I've had an exasperating day"; "her infuriating indifference"; "the ceaseless tumult of the jukebox was maddening"