Shaymuss

n.

Heard in Waterford

An unmerciful knee in the lateral thigh muscle causing temporary paralysis and excruciating pain.

In use

Ah ref he only barely gave him a shaymuss and he went down like a sack of spuds...

Posh English

Good referee, the fellow merely administered a gentle knee strike to the thigh and the chap collapsed like a sack of potatoes.