What is Gronka?
1.
A particularly large or sticky bogey characterised by its obstinacy and reluctance to be removed.
For fuck's sake, that gronka was so big, I needed a shovel to get the bastard out - I felt like I was pulling my brain out of my nose!!!
Gerald flushed crimson with embarrassment as Hermione gestured delicately towards the abseiling gronka swinging from Gerald's nostril, "Gerald dearest, may I draw your attention to the giant green bat hanging from your cave"
See