Delta 9 THC

THC (or Delta 9 THC) is the active compound in cannabis that causes you to feel high. The compound is the main reason people consume cannabis, either for fun or for medical benefits. When you smoke, vape, eat an edible, or do a dab, you can thank THC for the high. THC’s scientific name is delta-9-tetrahydrocannabinol, or delta-9 for short. Delta-9 is a cannabinoid. The cannabis plant contains many cannabinoids and terpenes, plus other compounds. Cannabinoids in the plant (phytocannabinoids) interact with cannabinoids in the body (endocannabinoids) to cause effects and make you feel high.

Source: https://www.leafly.com/news/cannabis-101/what-is-delta-9-thc