According to the announcement post Introducing Arqade!Introducing Arqade!, it was suggested in a community chat room about the topic:
We recently have put a lot of effort in coming up with a unique brand name for this community. As you know, naming is hard! After numerous brain storming sessions, we found a great name(and was able to obtain the domain name). It was suggestedsuggested in a community chat session, and "Arqade" was chosen. "Arqade," obviously playing off the word "arcade," reflects what this site is about. It's a place where gamers hang out, answer each other's questions or simply chit in the chatroom. As a bonus, "Arqade" even contains the acronym "QA" in it!
Before this chat took place, there were suggestionsuggestion postsposts for coming up with a good name, however according to the meta post Chat room for suggesting a new name for Gaming.SEChat room for suggesting a new name for Gaming.SE:
We took these suggestions into consideration, and have gone through several rounds of brainstorming to try to come up with alternatives. Unfortunately, many of our ideas for new domain names are unavailable.
A set of criteria was defined for suggesting names and the chat room was opened for suggestions.
The rest, as they say, is history.
