look up any word, like sweetest day:
 
1.
Cardy...a cardigan.

Essential northern clobber
"It`s a bit nippy outside, our Terry. You`d better pop yer cardy on if yer goin` out"
by Dr Fox May 08, 2007
 
2.
A cardy is a piece thin piece of cardboard rolled onto a cylinder, and used a filter in marijuana cigarettes. Its purpose is to prevent on inhaling ash and plant matter while toking particularly in the case of blunts and fat marijuana cigarettes. The use of a cardy also prevents the formation of a roach (see roach definition).
"roll a cardy in that joint man"
by asmodeus_82 April 17, 2008