Am I the only person in Thailand who doesn't have a gik?

So last weekend i was teaching a bunch of creepy old male principals (not by choice, mind you) and I asked them if they visit with their family on the weekends. They all said, "Oh yes, I visit my parents, my children, my gik." I was like, "What's a gik?" Apparently it's someone's girlfriend/boyfriend on the side. But it's not like a secret mistress cause everyone knows about your gik. Lots of married Thai men have young boyfriends or girlfriends on the side and I guess some Thai women have giks though it's not as common. I haven't really gotten to talk to a lot of Thai people about this topic. I just wonder if it's really accepted, looked down on or what. I don't necessarily think it's wrong but I think it's interesting. And the minute i learned about giks, I started hearing the word everywhere I went. I think that one of the problems is that this country has such a problem with AIDS and a lot of tThai men get AIDS from their giks and pass it on to their wives. I'm thinking about volunteering to work with some of my friends who teach classes about AIDS to people in hill tribes.