Don't call me a turtle egg!
One of the more colourful insults I've come across is wángbā 王八 or wángbā dàn 王八蛋, literally meaning turtle or turtle egg. It roughly translates to 'bastard', 'jerk' or 'son of a bitch'.
The turtle the insult refers to is the Chinese soft-shelled turtle. It has a snub nose, is kind of funny-looking and is farmed here in the millions (Wikipedia estimates at least 100 million per year) and sold as a delicacy, mostly for use in soups. I can confirm they're found in almost all wet markets, where they lie in large basins, awaiting their brothy demise.
There's another word for hard-shelled turtles/tortoises: wūguī 乌龟. When I asked whether wūguī were eaten, she looked at me as if I'd asked to eat her housecat. So, no, it seems.
Back to the insult. There are a couple of theories about its origin. My preferred one is that wángbā dàn and wàng bā duān 忘八端 are roughly homophones, wàng meaning to forget and bā duān referring to the eight characteristics of an upstanding man. They are - bear with me - as follows: xiào 孝, tì 悌, zhōng 忠, xìn 信, lǐ 礼, yì 义, lián 廉, chǐ 耻, or filial piety, loyalty to one's older brother, devotion, faithfulness, courtesy, righteousness, integrity, and shame. They're the uber-traditional Confucian virtues, most of which are still relevant today. So, saying someone has forgotten these eight virtues is basically calling them uncouth. Nice.
The other theory holds that in the past, people believed male turtles couldn't reproduce, and female turtles could only do so by mating with snakes. Therefore, male turtles had to depend on prostitutes for their livelihood (...naturally?). The word dàn (from wángbā dàn) is apparently northern Chinese slang for testicle, which is a fairly universal insult... particularly if it's the testicle of someone who often cavorts with prostitutes.
In terms of usage, it was introduced to me in an incident of road rage that almost came to blows, with one man getting annoyed at another's parking ability and calling him wángbā. Some native speakers have told me it's still a valid insult, but feels a bit dated - similar to how 'idiot' and 'jerk' were genuinely quite harsh insults in the 60s and 70s. Saying them on evening TV might get your show in hot water, that sort of thing. But they've now been normalised. A cursory search of Chinese internet swearwords does indeed bring up much more explicit zānghuà 脏话 profanity (lit. dirty speech). But I find the history of the turtle is far more colourful.
Next time, more of... whatever this was.