Gotchies
When I was a youngster, my brothers and I grew up calling our underwear “gotchies.” That sounds like a ridiculously strange word. We got it from Mom, because that's what Mom called them. Does anyone still use that word? I never wondered about its origin. I just accepted it. Later I heard the word “tighty-whities” on U.S. TV shows and immediately understood it. But I have always disliked “tighty-whities” for the same reason I hate the word “panties.” I mean, if you're going to talk about something, you might as well use the proper vocabulary. Don't be infantile about it and use silly words instead.
There are other, somewhat similar euphemisms used for underwear, like “gatchies,” “gatch,” “gitchies” and “gitch.” These appear to be somewhat related, and I suspect they are somehow related to children at summer camp, spreading the vocabulary among themselves in a camping environment. Then there are the classics like “skivvies,” “knickers,” and “bloomers,” and the most classic of all, “unmentionables.”
I read on the internet that the word gotchies comes from the Ukrainian word “gatky,” for underwear. I never heard that before. “Gotchies” is fun (and funny) to say, but it’s not really an appropriate conversation topic.