A pavement oyster not yet deposited. i.e. Still in production.
"I must be dehydrated or maybe I've got a cold coming on. I feel like I've got a big lump of chewing gum stuck up my nose. Cover your ears for a second, lads. I'm going to have a good old grockle and see if I can expel this paranasal tubercular sinus oyster."
by Piemanius May 15, 2008