Laggahead Share definition Flag A type of seaturtle with a masssive cranium. This word can also be used to describe a male genatalia. Very useful when trying to annoy teachers also. Coach, Look at this Laggahead seaturtle, its head weighs 15 tons! Its extremely wide also! Laggahead by Graham D September 8, 2008 0 0 Get merch Get the Laggahead mug. Buy Now — $32.95 See more merch