Dappy is one third of the group N-Dubz.
N-Dubz are from London.
He wears woollen hats.
Dappy - Na-na-na it's N-Dubz
Used to descripe a girl who is a bit dippy but also a bit mad or eccentric. Friendly mild insult.
Emily: So I locked my housekey in my locker again..
Jas: Your so dappy!
Doing something stupid and/or uneccisary.
Tom: I broke my arm on my trampoline
Louie: Your so dappy!
dappy is a term usually associated with certain types of girl. sometimes the person in question may be mad, loony, or in my own experience, a complete nutter.
that kirsten is dappy as fuck
A person that acts cool when they aren't or is unnecessarily loud in a public place.
John: you see that guy over there shouting at random people and acting like he's cool?
Steve: yeah, he's such a dappy
The splashback from a toilet when you take a shit, especially bad when it hits your asshole.
Damn that turd had some mad dappies.
a despicable or disgusting person
A: I raped your sister...
B: you Dappy cunt