THC

noun

ˌtē-(ˌ)āch-ˈsē

: either of two physiologically active isomers C₂₁H₃₀O₂ from hemp plant resin

especially : one that is the chief intoxicant in marijuana

When a person tokes, eats or vapes cannabis, a wave of THC, or tetrahydrocannabinol, washes into the brain. —Laura Sanders

THC, the main chemical component of marijuana, has been shown to reduce nausea and increase appetite in chemotherapy patients. —Andrew Weil

THC disappears from blood quickly as it is absorbed in the brain, making blood tests a more reliable measure of recent use but not a great correlate of impairment. —Eliza Gray

Examples of THC in a Sentence

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Determined to revive the historic brand, the entrepreneurs worked with a Miami craft distiller to develop a modern version inspired by the original, minus the THC. — Peter Burke, FOXNews.com, 16 Oct. 2026 Investigators allege Estrada Ramirez intended to rob Rangel of money, firearms and THC e-cigarettes. — Annasofia Scheve, San Antonio Express-News, 15 Oct. 2026 That must include the physical and mental health impacts of THC abuse. — Mary Ramsey, Charlotte Observer, 14 Oct. 2026 Rivera at the scene failed a drug test, with cocaine and THC, the psychoactive compound in cannabis, detected in his system, Katz said. — Rocco Parascandola, New York Daily News, 13 Oct. 2026 See All Example Sentences for THC

Word History

Etymology

tetrahydrocannabinol

First Known Use

1967, in the meaning defined above

Time Traveler

The first known use of THC was in 1967

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Thayer

THC

ThD

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Style

“THC.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/THC. Accessed 20 Oct. 2026.

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Medical Definition

THC

noun

ˌtē-ˌāch-ˈsē

: either of two physiologically active isomers C₂₁H₃₀O₂ that occur naturally in hemp plant resin or are synthetically prepared:

: one that is the chief intoxicant in marijuana and is used medicinally

called also delta-9-tetrahydrocannabinol, delta-9-THC

see dronabinol

: one that is present in marijuana only in minute quantities

THC

noun

Examples of THC in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Medical Definition

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