(as) thick as a brick

(as) thick as a brick

Remarkably stupid, dimwitted, or obtuse. I smoked a lot of marijuana when I was in high school, so I turned out thick as a brick by the time I finally graduated. Jen's new girlfriend is very nice, but she's as thick as a brick.
See also: brick, thick
Farlex Dictionary of Idioms.
See also:
  • be (as) thick as a brick
  • (as) thick as two planks
  • thick as two planks
  • thick as two short planks
  • (as) thick as two short planks
  • be (as) thick as a short plank