In the present context flat will obviously be one, and cat or drat will be another.
They mixes up alum, and bone-dust, and plaster of Paris, and—drat that door!
In the intervals of gathering brush for the fire and pouring sap into the steaming pan—which still leaked here and there, drat it!
I've had it every year since it became the fashion, drat it!
Theres some cloes ye kin be fixin up for Dan, whin yeve so much time as to be spindin it on Moody and Sankey men, drat em!
Diva grew very red in the face, and said “drat it” under her breath.
With one accord the four looked in the other direction, as Mr. Sloane, with a drat that pup!
Allow hisself to herd with them—well, drat it, there, I never did!
One way, you can't blame 'em for looking at it so, drat 'em!
Well, drat the boy, you'll stop and have a cup of tea, and a bit of seed cake.
1815, disguised form of exclamation God rot (something or someone).