What in tarnation?!?!

I had no idea tarnation was a portmanteau. I use it all the time. I always assumed it shared a derivation with Tarheels or beating the tar out of someone.

tarnation
1. noun
The act of damning or the condition of being damned.
2. interjection
Used to express anger or annoyance.

From tarnal, a variant of eternal, and damnation.

Tarheel
noun
A native or resident of North Carolina.

The term “Tar Heel” was originally a pejorative—much like the term “Georgia cracker”—that dates back to colonial times. North Carolina was the poorest of the 13 original colonies, and the state’s primary exports were naval stores—pitch and tar. “Tar Heel” was thus an insult levied at the state’s residents who were so poor and ignorant that they “walked around barefoot with tar on their heels”.

Of course, in this house, Tarheel still is a pejorative, but then, we're Duke fans.