\ ˈkəsp How to pronounce cusp (audio) \

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 How to pronounce cuspate (audio) , -​spət \ adjective
cusped \ ˈkəspt How to pronounce cusped (audio) \ adjective

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

The network previously ordered a pilot from showrunner Jane Goldman starring Naomi Watts that’s set thousands of years before the events in GoT when Westeros was on the cusp of The Long Night war with the White Walkers. James Hibberd,, "Game of Thrones prequel series about the Targaryens near pilot order," 12 Sep. 2019 These are exciting times for the Sacramento Kings, who are on the cusp of something because of the way De'Aaron Fox has come of age as a point guard. Rob Mahoney,, "Top 100 NBA Players of 2020," 12 Sep. 2019 As a result, Segev asserts, Jewish settlers were left unprotected during the Arab riots of 1929, and as late as 1947, on the cusp of Israel’s War of Independence, battalions were unready for battle. Diane Cole, Washington Post, "In Israel’s founder, many contradictions but a single-minded determination," 6 Sep. 2019 Adam was on the cusp of finally moving out of my parents’ house, into a home with five other adults with Down Syndrome. Alyson Pomerantz, Longreads, "Anaphylaxis of the Mind," 3 Sep. 2019 The inaugural Vines and Wines column for the Ramona Sentinel comes skidding in on the cusp of the grape harvesting season. Julie Gallant, Ramona Sentinel, "Vines & Wines: Rainy weather holds promise for robust harvest," 30 Aug. 2019 Case Western Reserve, coming off an 8-2 season, and Baldwin Wallace each received votes and are on the cusp of cracking the top 25. Branson Wright,, "Division II, III college football preview: Notre Dame College, Mount Union are in championship hunt," 31 Aug. 2019 Arsenal are on the cusp of having a major injury boost after the upcoming international break, with Héctor Bellerín, Kieran Tierney and Konstantinos Mavropanos set to return to full training next month., "Injured Arsenal Trio Set to Return Next Month as Rob Holding Features for Under-23s," 29 Aug. 2019 As of May, the F.E.C. had a backlog of nearly three hundred cases, some dating back to 2012, forty-five of which were on the cusp of a five-year statute of limitations that will toss them off the docket. Sue Halpern, The New Yorker, "Filling the Empty Seats at the F.E.C. Won’t Fix America’s Corrupt Elections," 29 Aug. 2019

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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Statistics for cusp

Last Updated

17 Sep 2019

Look-up Popularity

Time Traveler for cusp

The first known use of cusp was in 1585

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More Definitions for cusp



English Language Learners Definition of cusp

technical : a pointed end or part where two curves meet


\ ˈkəsp How to pronounce cusp (audio) \

Kids Definition of cusp

: a point or pointed end the cusp of a tooth


\ ˈkəsp How to pronounce cusp (audio) \

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 How to pronounce cuspal (audio) \ 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).


formidable, illustrious, or eminent

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