cusp: Meaning and Definition of

cusp

1. a point or pointed end.
2. a point, projection, or elevation, as on the crown of a tooth.
3. Also calleda point where two branches of a curve meet, end, and are tangent.
4. a decorative device, used esp. in Gothic architecture to vary the outlines of intradoses or to form architectural foils, consisting of a pair of curves tangent to the real or imaginary line defining the area decorated and meeting at a point within the area.
5. a point of a crescent, esp. of the moon.
1. the zodiacal degree that marks the beginning of a house or a sign.
2. Informal.a person born on the first day of a sign.
7. a point that marks the beginning of a change: on the cusp of a new era.