Literally:
* The thick fog made it impossible to see the road.
* He spread a thick layer of butter on his toast.
* The forest was so thick with trees that it was hard to find our way through.
Figuratively:
* She has a thick accent that I can barely understand.
* He has a thick skull; he never learns from his mistakes.
* The air was thick with tension as they waited for the results.
* She had thick eyelashes that framed her beautiful eyes.
* This is a thick book, it will take me a while to read it.
Idiomatically:
* He's thick as two short planks; he doesn't understand anything.
* She's thick in the head, but she has a good heart.
* They were thick as thieves and always got into trouble together.
The meaning of "thick" can vary depending on the context. So, pay attention to the surrounding words to understand the intended meaning.