This French word is tossed around a lot in the wine world, but it's actually pretty useful if you know what it means. Terroir means everything environmentally that affects how a grape grows: rainfall, sunshine, temperature, soil, altitude, etc. All of these elements influence the flavor of a wine.  Since terroir is very unique, the same variety of grape can taste quite different from one place to another. Think of a Chardonnay from France versus one from Napa.