look up any word, like twoosh:
A guy who is not cool enough to have a 1997 Subaru Outback, especially not a white one.
Why is his car not a 1997 Subaru Outback?
Because he's Duncan.
by ndawg696969 February 26, 2014
The pile of shit left beside the toilet at Myers by some punk ass kids.
The act of crapping on the floor, to annoy other patrons and janitorial staff of public washrooms.
I was out grocery shopping with the old lady and wet to the can. Some jerk laid a Duncan.

Just for kicks, my buddy left a Duncan at a Walmart.
by Dynamite65 July 20, 2014
a penis
a duncans a penis
by Huktast April 10, 2011
A twat who loves himself. You just know a Duncan when you see one.
"omg, he's walking like a gay".
"he must be a DUNCAN"
by nfie August 24, 2011
Purposefully saving a bowel movement for when on the clock at work, thereby effectively getting paid for it.
"I'm gonna take a duncan then go on my lunch break."
by KoreRat January 24, 2014
One with a strong attitude. Someone who thinks they know it all.
Wow quit being such a duncan today.
by justinbitchbaby August 04, 2012