the.com/thick
The space between two surfaces, or two thoughts, depending on what you're measuring.
means Having significant distance between opposite sides; also dense, abundant, or, slangily, unintelligent.
from From Old English 'thicce,' meaning dense or solid, a word so sturdy it barely changed in a thousand years.
insult dutyCalling someone thick means dim since the 1500s.
thick asClose friends are 'thick as thieves' since 1800s.
body slangModern admiring sense flips it to compliment entirely.