\ˈkəsp \

Definition of cusp 

: point, apex: such as

a : a point of transition (as from one historical period to the next) : turning point also : edge, verge on the cusp of stardom … you're on the cusp between heat exhaustion and life-threatening heatstroke. — Mark Jannot

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 (see foil entry 2 sense 4)

e(1) : a point on the grinding surface of a tooth

(2) : a fold or flap of a cardiac valve

Illustration of cusp

Illustration of cusp

1 cusp d

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Other Words from cusp

cuspate \ˈkə-ˌspāt, -spət \ adjective
cusped \ˈkəspt \ adjective

Synonyms for cusp


apex, end, nib, nose, pike, point, tip

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Examples of cusp in a Sentence

the cusp of a tooth medical researchers who are on the cusp of a major breakthrough

Recent Examples on the Web

Entering his third season with the Indiana Pacers, the former Michigan Wolverine was on the cusp of firmly establishing himself as a solid rotation player in the NBA. Vince Ellis, Detroit Free Press, "Detroit Pistons Glenn Robinson III coming for starting forward spot," 14 July 2018 Now 52 and 53, Patrice and her husband, Dan, are on the cusp of a new life stage — three of their five children are now financially independent young adults, and the two kids at home are just a few years away from graduating high school. Stephanie Walden, USA TODAY, "How to find balance and get your retirement plan back on track," 13 July 2018 To facilitate his son’s racing career, Jones’ late father, Dave, sold a classic 1965 Corvette when his son was on the cusp of becoming a teenager. Edgar Thompson,, "Emotion-filled 22-year-old Erik Jones captures chaotic Coke Zero Sugar 400," 9 July 2018 Belgium’s elimination of Brazil at the World Cup puts its cast of stars on the cusp of reaching the final and matching lofty expectations. Steve Douglas, Houston Chronicle, "England defeats Sweden to reach World Cup semifinals," 8 July 2018 Scott, who is on the cusp of an age in which homosexuality will be more accepted, has repeatedly had to suffer being silenced and erased, and ultimately dragged through press coverage. Karen Han, Vox, "How A Very English Scandal spins sensationalism into empathy," 7 July 2018 On the cusp of breaking into the mainstream Nick Goeser is not discouraged. Emily Hopkins,, "Your produce is less healthy than it was 70 years ago. These farmers might change that," 4 July 2018 The Bengals have been on the cusp of moving deeper into the playoffs the past few seasons. Dennis Hohenberger, Courant Community, "Chris Baker Visits Bart's Drive-In," 3 July 2018 Naby Keïta was on the cusp of joining Bayern Munichbefore being talked into a move to Liverpool by Sadio Mané, according to Times journalist Paul Joyce., "Report Claims That Naby Keita Was Talked Out of Bayern Munich Switch By Liverpool Winger," 30 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cusp.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of cusp

1585, in the meaning defined above

History and Etymology for cusp

Latin cuspis point

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Phrases Related to cusp

on the cusp

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Time Traveler for cusp

The first known use of cusp was in 1585

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English Language Learners Definition of cusp

: a pointed end or part where two curves meet


\ˈkəsp \

Kids Definition of cusp

: a point or pointed end the cusp of a tooth


\ˈkəsp \

Medical Definition of cusp 

1 : a point on the grinding surface of a tooth

2 : a fold or flap of a cardiac valve

Other Words from cusp

cuspal \ˈkəs-pəl \ adjective

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More from Merriam-Webster on cusp

Thesaurus: All synonyms and antonyms for cusp

Spanish Central: Translation of cusp

Nglish: Translation of cusp for Spanish Speakers Encyclopedia article about cusp

Comments on cusp

What made you want to look up cusp? Please tell us where you read or heard it (including the quote, if possible).


lying above or upon

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