Definition of "bedad"

Lady O'Dowd is also so attached to it that, she says, if anything were to happen to Mick, bedad she'd come back and marry some of 'em.

1848, William Makepeace Thackeray, Vanity Fair‎

But as for the party, bedad, it's rotten to the core, and won't stand another session.

1867, Anthony Trollope, Phineas Finn‎

"Ah, bedad, ye can finish it yourself--it's too expansive for me!"

1875, Mark Twain (Samuel Clemens), Sketches New and Old‎

May I tempt you to a little more filleted lemon sole, miss Dubedat? Yes, do bedad. And she did bedad.

1922, James Joyce, Ulysses‎