A sex position in which two individuals kneel on all fours with their rear-ends facing one another share a two-headed dildo; the beauty of an eighty-eight (or 88) is that it can be shared by any two people regardless of their respective genders.
I love the coke-party scene from "Requiem for a Dream" when Jennifer Connely does an eighty-eight with that blonde chick!!
The eighty eight was a weapon in the German army in World War Two. Actually an anti-aircraft weapon firing an 88 mm shell, the 88 had a major advantage in range over many Allied artillery pieces. German gun crews fighting in the Spanish Civil war turned the gun on approaching tanks that had broken through their lines - unsure how effective they would be. Germans quickly converted the gun to anti-tank use, putting the gun into their vaunted Tiger Tanks. Allied tanks were knocked out before they were able to get close enough to use their weapons. The eighty eight had a self ejecting shell and were deployed in numerous configurations including tanks, self propelled guns, and a four legged gun that was towed behind a vehicle. They were less effective at close range.
The German eighty eight picked off the Allied tanks before they could get into range.