内圆滚线...

n.圆内旋轮线，内摆线...

hypocycloidal的音标：hypocycloidal的英式发音音标为：[haɪpəʊsaɪk'lɔɪdl]hypocycloidal的美式发音音标为：[haɪpoʊsaɪk'lɔɪdl]...

hypocycloid的音标：hypocycloid的英式发音音标为：['haɪpəʊ'saɪklɔɪd]hypocycloid的美式发音音标为：[ˌhaɪpoʊ'saɪˌklɔɪd]...