: 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 Stability and Balance: Unlike THC, MIRA-55 maintained efficacy across a broader range of doses without losing effectiveness. Charlotte Observer, 15 July 2024 Richardson’s tenacity was tested when, after qualifying for the 100-meter race in 2021’s Tokyo games, her spot was rescinded after testing positive for THC and U.S.A., and Track and Field did not select her to run in the 4×100-meter relay. Mankaprr Conteh, Rolling Stone, 9 July 2024 According to the National Survey on Drug Use and Health, 27% of kids tried alcohol before the legal age and the National Institute on Drug Abuse reported in 2023 that sizeable percentages of eighth graders are testing drugs from vaping to THC. Christina Montoya Fiedler, Parents, 2 July 2024 According to the warrant affidavit, the lab test reportedly showed Zawadzki had THC, fentanyl, norfentanyl and Xylazine — a non opiate sedative — in his system. Justin Muszynski, Hartford Courant, 29 June 2024 See all Example Sentences for THC 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'THC.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

tetrahydrocannabinol

First Known Use

1967, in the meaning defined above

Time Traveler
The first known use of THC was in 1967

Dictionary Entries Near THC

Cite this Entry

“THC.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/THC. Accessed 25 Jul. 2024.

Medical Definition

: either of two physiologically active isomers C21H30O2 that occur naturally in hemp plant resin or are synthetically prepared:
a
: one that is the chief intoxicant in marijuana and is used medicinally

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

see dronabinol
b
: one that is present in marijuana only in minute quantities

More from Merriam-Webster on THC

Last Updated: - Updated example sentences
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