If someone is a plank then they're a bit slow or dense at the best of times; not the sharpest tool in the shed as the saying goes. If they r a chief plank then thats the next level of stupidity.
That bloke is the chief of all planks, what is he like?!
This geezer is as thick as two short planks, what a tit?!
by Raydon February 23, 2004
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