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noun \ˈkəsp\

: a pointed end or part where two curves meet

Full Definition of CUSP

:  point, apex: as
a :  a point of transition (as from one historical period to the next) :  turning point; also :  edge, verge <on the cusp of stardom>
b :  either horn of a crescent moon
c :  a fixed point on a mathematical curve at which a point tracing the curve would exactly reverse its direction of motion
d :  an ornamental pointed projection formed by or arising from the intersection of two arcs or foils
e (1) :  a point on the grinding surface of a tooth
(2) :  a fold or flap of a cardiac valve
cus·pate \ˈkəs-ˌpāt, -pət\ adjective
cusped \ˈkəspt\ adjective

Examples of CUSP

  1. the cusp of a tooth
  2. <medical researchers who are on the cusp of a major breakthrough>

Illustration of CUSP

Origin of CUSP

Latin cuspis point
First Known Use: 1585

Related to CUSP

CUSPATE Defined for Kids


noun \ˈkəsp\

Definition of CUSP for Kids

:  a point or pointed end <the cusp of a tooth>
Medical Dictionary


noun \ˈkəsp\

Medical Definition of CUSP

:  a point on the grinding surface of a tooth
:  a fold or flap of a cardiac valve
cus·pal \ˈkəs-pəl\ adjective


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