A all purpose cuss word, made famous by 'Red Dwarf' a popular TV show. Thought to have first been seen on a foreignappliance before being used in 'Red Dwarf'.
The origin of this word is unclear - while it is accused of being an abbreviation of "smegma," Grant Naylor insist that they saw the word on a foreign appliance, and co-opted it as an all-purpose cussword for their show "Red Dwarf."
Sheghead is another word for 'Nitty' or 'Crackhead', Sheg itself means taking the piss within the united kingdom where it originated from. The first person who said this word was a man on discord by the name of Oneil Brooks