A frantic dance a Geordie does when he has held it in too long. This usually occurs after one too many brown ales and a failure to visit the water fall grotto before leaving the pub or when small children have a sudden need to go.
(Mam) ..."Tommy is doing a diggy dance. Best get him to the toilet before he wets his pants!"
The act of stopping and digging straight down in order for refuge or resources (Minecraft and real life)
I was being chased so I had to do a diggy down to hide.