- cusp - point formed by two intersecting arcs (as from the intrados of a Gothic arch)
--1 is a kind of point
- cusp, leaflet - a thin triangular flap of a heart valve
--2 is a kind of flap
--2 is a part of heart valve, cardiac valve- cusp - small elevation on the grinding surface of a tooth
--3 is a kind of point, tip, peak
--3 is a part of tooth - cusp, leaflet - a thin triangular flap of a heart valve