The superlative form of 'thick,' meaning having the greatest extent from one side to the other, or most densely packed.
From Old English 'þicce,' Germanic in origin, the superlative adds '-est' to create the most extreme form.
The word 'thick' started as purely physical but evolved to mean 'stupid' or 'not intelligent' by the 1600s—showing how we use physical characteristics as metaphors for mental abilities, sometimes unfairly.
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