The four primary characteristics of coffee are: Acidity, Aroma, Body, and Taste.
Acidity
Acidity in coffee is expressed through sharpness of flavor profiles found around the edges of the tongue and towards the back of the mouth. The acidity of a coffee may be assessed as lively/active, mild/moderate, flat to dull, and should not to be confused with bitterness.
Aroma
Aroma is found through the nose and lands on the taste buds. The smell or bouquet of the bean shows from coffee when ground or while in liquid form. Coffee aromatics can be expressed as sweet to dry, complex to simple, floral to tropical, sweet to sour.
Body
This known as the “mouth feel” or how thick or thin you perceive the coffee to be. Specifically deals with the “depth of the liquid”, expressed through lightness or intensity of the weight the flavors you experience.
Taste
In addition to the “flavor” in a flavored coffee, there is also coffee taste. Taste refers simply to the taste of the coffee. Coffee can range from one-dimensional (as in a “straight” or single varietal) to rich and complex (as found in some blends). Look for specific taste elements described as winey, earthy, sweet, nutty, smoky, or spicy.