What is piss down? How to use in English

The expression "piss down" is an informal and at times vulgar English phrase meaning "to rain heavily," with an emphasis on the intensity and intensity of the rainfall. Originally, the phrase originated in the seafaring communities of England, where the saying "it's pissing down" was a common expression to describe heavy rainfall both aboard ships and on land. The literal meaning of "pissing down" is to urinate heavily or in abundance. Sailors, in particular, would use this expression to describe heavy rainfall because they noticed that rain was intense enough to mimic the same consistency and texture as urine. In addition, the rain was so heavy that it appeared to be "raining down" upon them, almost like a urine stream in motion. The exact origins of this expression are disputed, but it is likely rooted in the local dialects and slang of 18th-century England. The expression became popularized in the late 19th century, and by the mid-20th century it had become firmly entrenched in the English lexicon, appearing in literature, song, and everyday conversation. Today, the phrase "pissing down" remains in common use as a vivid and colorful expression to describe heavy rainfall, with all its original connotations still intact.