特殊用法beach cusp1.【地质】海滩嘴double cusp1.双尖点focal cusp1.焦(点)会(切)线keratoid cusp1.甲种尖点parabolic cusp1.抛物尖点cusp of a curve1.曲线的尖点cusp of the first kind1.第一类尖 点, 简单尖点cusp of the second species1.第二种歧点(自切点)