History of words and phrases
Havoc: From the Middle Age French word "havok," it was a war cry – a signal for the invading warriors to attack, sack and plunder a village.
Raining cats and dogs: This phrase goes back to the Middle Ages when people believed that cats and dogs had magical powers. Cats were thought to have a lot to do with storms and dogs with wind.
Like a bat out of hell: Moving extremely quickly or suddenly. The phrase came into use at the turn of the century and Charles Earle Funk later theorized that bats avoid light as if it were cast by the fires of hell.