Special K

noun

slang

: the anesthetic ketamine used illicitly in powdered or liquid form

Word History

Etymology

after Special K, proprietary name of a breakfast cereal manufactured by the Kellogg company

First Known Use

1986, in the meaning defined above

Time Traveler

The first known use of Special K was in 1986

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Style

“Special K.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Special%20K. Accessed 5 Feb. 2026.

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Medical Definition

Special K

noun

Spe·cial K ˈspesh-əl-ˈkā

slang

: the anesthetic ketamine used illicitly in powdered or liquid form

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Special K

noun

Word History

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Medical Definition

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