Riding a downhill mountain bike with full suspension down a hill very rapidly, into large sums of roost and loamy soil formations. May also include riding over large rocks and slimy roots at mach10.

You say this when something is too sick to just be "sick." Reserved for only the SICKEST things in life.

a mean spirited bad ass

Used when hearing something such as a story or some news to show that it is awesome and that you are not kidding.
Extended version of gnar gnar for real real.
English translation: Its awesome, for real. I'm not kidding.

Downing a couple bottles of robo and getting pry leaned with yr bros watching 'it's always sunny in philidelphia' on yur macbook pro.

Symptoms include inability to control basic motor functions and extreme disorientation.

gnarly in the most extreem sense (Is also a band name)

gnar, beyond what the comon man can comprehend, simply the highest ranking of gnar(gnarly)