Death Grunt 

A vocal style, mostly used by death / black metal bands. It is a very deep guttural sound, made from the back of the throat. Bands such as Cannibal Corpse and Morbid Angel use it as their sole vocal style, while bands like Opeth, In Flames and Dimmu Borgir use it alongside a more melodic singing voice.
Not to be confused with the Screeching, with is used by bands such as Darkthrone and Cradle Of Filth (who also use death grunts).

The new Paradise Lost record has less of the death grunts that filled their early work.

Death Grunt by StigmataMartyr July 30, 2004

Death Grunt 

a vocal style used by poser bands to appear hard. What was once a cool NEW idea has been taken over by crappy little pretentious posers acting tough. They can't sing so they don't even try, thus producing crap.

Death Grunt is also knows as Cookie-Monster vocals because it sounds like the cookie monster from sesame street is doing the vocals.

Death Grunt by Bubba Backwater October 15, 2006