An expression of great misfortune, expanded from it's original meaning, to be pregnant. The expansion is due to the expression often being the unfortunate case of the pregnancy being untimely and unpredicted.
"When they find all the coke in Mark's desk, he's gonna be sooooo up the duff!"
"Shit, I've got 2 flats and only 5 minutes to get the airport!"
"You are up the duff mate"
To be pregnant.
It was very embarrssing for Kevin when he got Peggy up the duff, but it served him right for trying to save money by using a flak jacket
Pregnant, usually unplanned.
She's up the duff and really confused right now.
1. The slang term for being pregnant
2. A drinking toast with Duff beer in the Simpsons
Example: She’s uptheduff again
Example: I’ll uptheduff to payday, to dooh