the.com/blockhead

A skull so dense even your bad ideas need a running start.

means An obstinately stupid person — someone slow-witted or thick-headed.

from A straightforward 16th-century compound of 'block' (a solid chunk of wood, like a hat-maker's wooden head-mold or a chopping block) plus 'head' — the image being a head made of wood, good for nothing but holding its shape. Related insults followed the same logic: blockish, wooden-headed, thick as a plank — all trading on the idea that a block of wood can take a shape but never a thought.

origin
18th century insult for wooden-headed stupidity
shakespeare used it
in title characterizing dull-witted fools
synonym squad
dunce, numbskull, dolt, all equally unflattering
charlie brown link
peanuts kids called him blockhead constantly
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