"Dagnabbit" is a hilarious word that you probably learned from Yosemite Sam. It's a pseudo-swear word you can use in public when you don't want to be technically blasphemous, like gosh, golly, gee, and other substitutes. But in even broader terms, it's a "taboo deformation," and the term applies to more words than you might think.
“Taboo deformation is one possible way for a word to change its meaning,” says Andrew Byrd, a professor of linguistics at the University of Kentucky who specializes in Indo-European languages. Basically, we are scared of the true names of certain beings or concepts, because to use them might mean we summon them, which we don’t want, or anger them, which we definitely don’t want, or simply make other humans mad at us, which is slightly less bad but still not ideal. The true name is powerful, and we normal humans can’t handle that power. So we avoid using the true name, but sometimes we still need to communicate with each other about those beings or concepts. That means we have to figure out a way to talk about something without using the actual word for it.
You can understand the concept when it applies to one's deity, or even multiple deities, but it also applied to more secular names, like "bear" and "wolf." Dan Nosowitz gives us a breakdown of how those words came to us through taboo deformations, as well as other terms such as "dagnabbit."
(Illustration: Aida Amer)