I checked it on the BaiDu website. Here is the story. AA is stand for Acting Appointment. It invented by the merchants of Netherland and Venice. During sixteenth and seventeenth century， the merchants of Netherland and Venice had frequently socials for their business. They Netherlanders thought if they treat the bill, but actually they have a few rate to see each other in the future. It seems not fair at all, so they prefer pay what you eat by yourself than treat. Also it could save your money. AA is stand for All Apart in HK. -------------------------------------- Dear duguup, I hope you can understand what I'm saying. It's so hard to me to translate the story very well. If you find some issue on my comment, pls correct. Thank u!

I learned in Chinese class that "AA" means "going dutch," to pay your own portion of the bill.

Let's go fifty-fifty.I think it comes from the Netherlands

AA comes from USA, it stands for "shAre equAllly" ,and no other special meaning in china

AA - Algebraic Average. It is comes from UK. And AA in Hongkong is also means "all part".