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like a cow pissing on a flat rock en · ADV

Compare piss down, piss it down, and French pleuvoir comme vache qui pisse (“rain like a pissing cow”).

(US, not-comparable, of rain or other liquid falling, vulgar) Heavily; copiously (and often loudly).
- It was pouring like a cow pissing on a flat rock. Would he show? She didn't know if he would or not, but the cows still had to be fed. Heaving herself out of bed, she threw on her rattiest jeans and a baggy tee and trudged out to the rain-soaked pastures, […] 2016, Victoria Vane, Beauty and the Bull Rider, Lyrical Shine, →ISBN:
- It poured like a cow pissing on a flat rock. Summer thunderstorm in a Catskill cattle pasture with 350,000 Mud People standing in it. Aerosmith was supposed to play at midnight, but midnight came and went. 1994, Albert Watson, Woodstock '94: the book, St Martins Pr, →ISBN:
- We hadn't gone a mile before it started to rain, light tentative drops at first, like unsure messengers. Then the lightning started and rent open the clouds. It came down like a cow pissing on a flat rock. We had no slickers and were soon soaked. 2004, James Corwin, A Grizzly Way to Die, →ISBN:
- Rita's car was an old Plymouth Fury that, despite the meticulous attention given to its lubrication system, leaked oil like a cow pissing on a flat rock. Nel and Danny got into the pickup truck and followed the trail of black ooze, all the way down ... 2014, Barbara Hall, Close to Home: A Novel, Open Road Media, →ISBN:

fr comme vache qui pisse (heavily — see also rain cats and dogs, piss it down)