What is the flavor of Thyme? What chemicals give it this flavor?
Thyme is dominated by the phenolic compound thymol, with the terpenes pinene, cymene, and linalool adding additional pine, citrus, and flowery flavors, respectively.
Source: On Food and Cooking (revised edition), pp 391, and table on 392. If you're into the chemistry of flavor, I highly suggest buying a copy, because the same table lists main flavor compounds for dozens of common ingredients and flavorings.