Originally a military term describing a disorganized situation with pending dissappointing results, 'ClusterShag' is used when describing such situations when profanity is not tolerated.
Gained popularity on late night television(The Daily Show) when recounting the actions leading up to the 2010 UK elections.
Office Manager: "The computers are down, our receptionist called in sick, the fax machine is on the fritz and the auditors will be here in 20 minutes. We're Screwed!!!"
Employee: " I know. It's a virtual clustershag of endless possibilities"
Similar to Clusterfuck except it's full of shit. (not just feces)
This gives a person more of an agony and WTF on their moment.
If you know about Clusterfuck being how chaotic it is, wait till you knew about Clustershit which means it is just exactly like it except it's full of shit.
A construction goes well but suddenly some mistake made it happen and considered a clusterfuck but it goes worse when many "shits" add up. Thus, it is named Clustershit.