Thick

n.

Heard in Down and Offaly

Generally used to describe someone who is not the sharpest pencil in the box, but can also be used to describe someone with a short fuse.

In use

Yer mawn yonder is fiersche thick, he keeps getting thick with me for callin' him names!

Posh English

That fellow over there is exceedingly dense, and he continually loses his temper with me for calling him a pastry.

Same phrase, other counties