hypocycloidPronunciation: /ˌhʌɪpə(ʊ)ˈsʌɪklɔɪd/Definition of hypocycloid noun Mathematics the curve traced by a point on the circumference of a circle which is rolling on the interior of another circle. Derivatives hypocycloidalPronunciation: /-ˈklɔɪd(ə)l/ adjective hypocycloid in other Oxford dictionaries Definition of hypocycloid in the US English dictionary