I was surprised to see this writeup in the "
New Writeups", because it is an insult in
Chinese.
Having an "ass like a chicken" means that you have a huge ass and this insult is usually used by women against women.
There's also having an "ass like a duck" which would be the direct translation, but having an "ass like a chicken" could also mean "having the ass of a whore" since chicken (or hen) is a vernacular for "whore." Originally a Cantonese insult, but it has been Mandarinized and can be used in Mandarin as well. Duck, by the way, in Cantonese is also slang for "Gigolo" and don't ask me why.
Either way, it's an insult.