metonymy
me.ton.y.my \m*-'ta:n-*-me-\ n [L metonymia, fr. Gk meto-nymia, fr. meta- + -o-nymi]a -onymy : a figure of speech consisting of the use of the name of one thing for th at of another of which it is an attribute or with which it is associated (as in "lands belonging to the crown")