These are some of the key concepts and words used to describe flavors. It is important to understand some of the nuance about these terms as it is very difficult to communicate flavor through language. The more terminology the more nuanced one can communicate the properties of a flavor and categorize the flavor in terms that are communicable.

Palate- The ability to appreciate flavor, this is often used both to describe foods that are preferences as well as the ability to distinguish detail.
Herb- Most often leaves and flowers of plants for flavoring usage that are preferred to be fresh and undried, a subset of spice that gives more clarity to the part being fresh.
Spice- Any plant part used primarily to impart flavor to food, also used to indicate the plant part is dried, herb is preferable to indicate fresh plant parts, but the terms are mostly interchangeable.

unpalatable- Describes when something tastes bad to the degree that no one wants to eat it, this is not an indication something is toxic, and is often confused with toxicity
Toxicity- When something is unsafe to eat, as well as the degree, and reasons that it is unsafe.
Edibility- Some plant parts are only edible after processing, or in certain forms, this effects the edibility and use of those parts.

These are effects on the palate, where one feels a sensation often accompanied by a flavor.

Astringent
Tannin
Numbing
Spicy
Piquant- The English language lacks nuance when describing something as spicy as in flavorful versus spicy as in producing a hot feeling on the palate.
Insipid- lacking flavor or lacking balance in flavor when flavors taste nondescript, for instance because too much is going on at the same time. Can occur as a side of effect of Piquant and Numbing effects.

Bitter
Sweet
Savory
Hearty
Salty
Sour

Fatty
Vegetal Herbaceous Medicinal Floral Powdery