look up any word, like basic bitch:
"Grandad dribbles" is the term used to describe when one does not shake their penis a sufficient amount of times after urinating, resulting in urine dribbling from the penis and down the individual's leg.
1. Yo man I just had the worst grandad dribbles!
2. You should of shaken more, bro.
by daveWORST January 31, 2011