Cat on hot bricks

To behave like a cat on hot bricks is to be very nervous, skittish or ill at ease, as a cat would be if walking on hot bricks. The expression dates from the mid-18th century and is a more modern version of the older British expression, a cat on a hot bake stone, which dates from the 17th century but is no longer in use. A cat on a hot tin roof is the American version that dates from the 1950s, from around the same time as Tennessee Williams’ play of the same title. It is not certain that Williams coined the expression but he most certainly made it popular.