kap·​pa | \ ˈka-pə How to pronounce kappa (audio) \

Definition of kappa

: the 10th letter of the Greek alphabet — see Alphabet Table

Examples of kappa in a Sentence

Recent Examples on the Web

Researchers have identified two others, kappa (κ) and delta (δ). Jonathon Keats, Discover Magazine, "Building a Better Painkiller," 11 May 2018 By activating only the kappa receptor, the chemical shouldn’t cause any of the side effects associated with the mu. Jonathon Keats, Discover Magazine, "Building a Better Painkiller," 11 May 2018 These receptors come in three flavors: mu, delta and kappa. Jon Kelvey, Smithsonian, "America’s Long-Overdue Opioid Revolution Is Finally Here," 13 Jan. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'kappa.' 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 kappa

15th century, in the meaning defined above

History and Etymology for kappa

Middle English, from Greek, of Semitic origin; akin to Hebrew kaph

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Dictionary Entries near kappa

kapok oil

Kaposi's sarcoma






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Time Traveler for kappa

The first known use of kappa was in the 15th century

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More Definitions for kappa


kap·​pa | \ ˈkap-ə How to pronounce kappa (audio) \

Medical Definition of kappa

: a cytoplasmic factor in certain paramecia that mediates production of paramecin and thereby makes the medium in which such microorganisms are grown toxic to members of strains not possessing the factor — see paramecin

More from Merriam-Webster on kappa

Rhyming Dictionary: Words that rhyme with kappa

Britannica.com: Encyclopedia article about kappa

Comments on kappa

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


a strong desire or propensity

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