To go for something in all forms. Popular in desert racing referring to blasting and jumping all over the place. Is also applied to anything super extreme. Can refer to sexual activities or be used as a motivational phrase.
Pete: Jump doesn't look good, we're probably going to die as soon as we land.
Tom: Don't be such a pussy! GET IT! GET IT!
"Man, did you see Nick turning Katie's pants blue? He was GETTIN IT.