Definition of cork:
made from, or consisting of, cork
"look at that cork statue."
the bark of the cork oak
, which is very light and porous and is very good for making bottle stoppers and insulation material; a bottle stopper made from this or any other
"it is hard to call it wine with a straight-face, when the cork is made of plastic."
or stop up, especially with a cork stopper; to leave the cork
in a bottle after attempting to uncork
"he was so loud I told him to cork it."