A sound effect used to describe a unpleasant occurance or appearance etc. Much like the sound of a foghorn.
Someone extremely hungover walks into the room and the only way to describe them is simply "dernt".
by Boyle265 January 14, 2009
Fat or Large. Comes from the drum sound effect often associated with a large zepplin or airship coming into a scene in older movies. Same sound can also be heard in Super Mario Brothers 3, on any airship level.
Damn that football player is dernt.
by ssftable September 29, 2003