: 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 As of July 1, individuals 21 and older can legally use, possess and consume up to 1.5 ounces of cannabis flower, 12 grams of concentrated cannabis, or a total amount of cannabis products that does not exceed 750 mg of THC in Maryland. Sherry Greenfield, Baltimore Sun, 10 Sep. 2023 The Benefits of Delta-8 The benefits of delta-8 THC are not as extensively studied as those of delta-9 THC or other cannabinoids like CBD (cannabidiol). Amber Smith, Discover Magazine, 9 Sep. 2023 The saleswoman recommends Bedtime Betty’s, a cannabis fruit chew, with doses of the cannabinoids THC, CBD, and CBN. Erick Trickey, BostonGlobe.com, 22 Aug. 2023 But she was suspended and missed Tokyo after testing positive for THC, the chemical in cannabis. Nick Zaccardi, NBC News, 21 Aug. 2023 One of those compounds, delta-8 THC, offers a less-potent alternative to delta-9 THC, which is the primary psychoactive compound found in marijuana. Dale Ellis, Arkansas Online, 21 Aug. 2023 Derived from hemp, Delta 8 THC is a cannabinoid that offers a milder psychoactive experience compared to its cousin, Delta 9 THC. Amber Smith, Discover Magazine, 12 Aug. 2023 The bill would have allowed patients to get a prescription for products like edibles and oils, which contain low amounts of THC. Irving Mejia-Hilario, Dallas News, 8 Aug. 2023 Broad-spectrum: Benefits: Retains beneficial cannabinoids without THC content, suitable for those who want to avoid THC. Drawbacks: May not provide as robust an entourage effect as full-spectrum options. Amber Smith, Discover Magazine, 4 Aug. 2023 See More

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



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 23 Sep. 2023.

Medical Definition

: 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

More from Merriam-Webster on THC

Last Updated: - Updated example sentences
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