Few English idioms are as strange, or as widely used, as “it’s raining cats and dogs.” Anyone learning English quickly discovers this phrase, usually with a puzzled look on their face. After all, animals do not literally fall from the sky during a storm. Yet native speakers use this expression casually to describe extremely heavy rainfall. So where did such an odd saying come from? The truth is that nobody knows for certain, but there are several fascinating theories that try to explain its origin.
The Norse Mythology Theory
One of the oldest and most popular theories connects the phrase to Norse mythology. In old Scandinavian legends, the god Odin was associated with storms, and he was often pictured together with dogs and wolves, which came to symbolize wind. Meanwhile, witches who were said to transform into cats were linked to heavy rain. Over time, storytellers and poets may have blended these two animal symbols into the single image of “raining cats and dogs,” using it to describe wild, stormy weather.
The Language Theory: “Catadupe”
Another theory looks not at mythology but at language itself. Some scholars point to an old, rarely used word, “catadupe,” which meant “waterfall” in earlier forms of English and had similar roots in Latin and Greek. According to this idea, saying that it was “raining cats and dogs” was really a playful way of saying it was raining like a waterfall. Over centuries, as the original word “catadupe” faded from everyday use, people may have unconsciously reshaped the phrase into something that sounded familiar, cats and dogs, since these were common household animals.
The Flooded Streets of England
A third, less charming explanation is tied to city life in seventeenth and eighteenth century England. During this period, many towns had extremely poor drainage systems. When storms hit, the streets would flood, and the rushing water would often sweep along the bodies of dead animals, including stray cats and dogs, that had drowned in the flood. After a storm passed, it was not unusual to see these unfortunate animals scattered through the streets, giving the impression that they had fallen from the sky along with the rain.
Early Historical Evidence
Historically, the earliest known appearance of a similar phrase comes from 1651, when the poet Henry Vaughan described a roof strong enough to survive rain in which “dogs and cats” fell in showers. Shortly afterward, in 1652, the playwright Richard Brome used a comparable line in one of his plays. Eventually, the phrase gained lasting popularity in the eighteenth century thanks to satirical writing that made fun of exaggerated conversation among the upper class.
Even though modern researchers admit that the true origin remains unclear, the idiom has survived for centuries, passed down through literature, conversation, and popular culture. Today, it is one of the most recognizable expressions in the English language, used by both native speakers and learners to playfully describe a heavy downpour, proof that a phrase does not need a clear history to become a lasting part of everyday speech.
