An area encumbered by heavy ass gas that will not disperse and one you must traverse through. Also, the depositor of said gas usually did so with an S.B.D. (silent but deadly) fart.
"Beef Thicket" While strolling the aisle of your local supermarket you suddenly hit a wall of odor that makes the air taste thick and impenetrable, not unlike having your path obstructed by a row of thick thorn bushes. As you pass through the described area you will state " phew, beef thicket" and quicken your pace.