Noun: A contraction of the "can't" and "bugger all" - short form of "Can not do bugger all", the double negative and poor spelling being ironice references to the futility of anything that can be related to a Catherall
He's a complete catherall
No way, he catheralle'd that up completely
'e spellz lark a caverorl
Originally from www.dervman.com - the ultimate nerd site for the pursuit of utter pointlessness, now brought into generic use for any car driver whose quest for fuel economy (that's Gas Mileage for you seppos) overcomes any other requirement of praticality or enjoyment for a car.
Tends to either own a diesel driven car (DERV = DIESEL ENGINED ROAD VEHICLE) or spend all his time justifying the use of small petrol engines, silly air intake modifications, lean burn devices, ECU monitors etc.
He's nerdy enough to be a Dervman
If you buy the Mondeo you'll become a proper Dervman