A sexual act; an extension of the "Eifel Tower", but greater, thus the term "Great Pyramid." Involves the female on all fours giving to the first of four men doggy-style or anal, the second a blowjob and the last two hand-jobs. The four men all hi-five to create a pyramid shape. Also, a transitive verb meaning to partake in the nominal form.
Did you hear that Kelly Eifel towered those two dudes?
You thinks she's a slut? Brenda was in a great pyramid last night with half the baseball team.