0I'd say, based on the number of similes with "thick" in them, it's used here too.02br
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00He's thicker than two planks. He's as thick as a brick. 02br
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00(You might also hear someone say that a cold, or more likely cold medicine, is making them feel thick-headed. I feel that way when I wake up from a nap that wasn't long eough too.)0-