Here's why:

* Terpene: THC contains a terpene skeleton, which is a class of hydrocarbons found in plants, responsible for their aroma and flavor.

* Phenolic: THC also has a phenolic ring system, which is a group of organic compounds containing a hydroxyl group attached to an aromatic ring.

Therefore, THC is considered a terpenophenolic compound, combining features of both terpenes and phenols.