Grime music on the West side of the Atlantic ocean is an especially acquired taste. Technically, the best way to describe grime music is a blend of Dancehall, Hip Hop and Electro [Techno, Drum and Bass etc]. You can always tell it’s grime if the MC sounds slightly off of the beat, that’s just the way they flow to it.
Subjectively speaking, I would classify Grime as the resonance in between buildings when a car that drives by is bumping a hard ass beat. Grime is the sound of a subway [or a metro as they call it], it’s the sound of the sewers, it’s the sound of an alley way. When I first heard Grime about 6 or 7 years ago I can honestly admit I wasn’t feeling it. But the only thing that’s changed since then is that I moved to the city, and when you walking down the street with grime blasting in your ears you feel invincible.