These words are related but not interchangeable in meaning. Distinctive means "characteristic," "individual," "set apart": "the distinctive roar of a lion." Distinct means "clear," "plain," "definite," "unmistakable in its identity": "Oxygen has properties distinct from those of helium." Distinguished stresses the quality or characteristic of being eminent, outstanding, renowned: "This official has had a distinguished career in public service." What is distinct is clearly seen and not easily mistaken for something else; what is distinctive is something so set apart as to be conspicuous; what is distinguished is conspicuous by reason of excellence and distinction.
Dictionary of problem words and expressions. Harry Shaw. 1975.