brutal
A word used to describe how heavy or fast and extreme a metal band is i.e. Death Metal. Generally doesnt apply to any other kind of music apart from metal as it fits this genre best.
Basically it is used loosley to describe how good the band itself is.
Have you heard that new Vital Remains album?... 

its fucking brutal.

(or)

You guys heard ofbrutalized mortality...?

aww yeah they're pretty brutal.