Brut is a term that defines dryness levels in sparkling wines; it is most famously used for Champagne, but it is a common term used around the world for most sparkers.
While Brut means "dry" for all intents and purposes, it can actually be off-dry or even lightly sweet. The definition of Brut for Champagne is between 0-12 grams of residual sugar, so Brut actually describes a range of sensations.
No matter how dry a Brut sparkling wine actually is in technical terms, it is generally dry enough to serve at the dinner table with most foods.