Wiktionary
damnit
interj. (label en especially southern US) (misspelling of dammit English)
Usage examples of "damnit".
Damnit, Ced, this planet has enough deceptions to cope with without having to deal with a human one as well!
Damnit, you couldn't have flag officers in their mess dress sitting out there with two scroungy enlisted men in battle dress--especially those confounded chameleons--bringing up the rear!