WordNet (r) 3.0 (2006):

synecdochic
    adj 1: using the name of a part for that of the whole or the
           whole for the part; or the special for the general or the
           general for the special; or the material for the thing
           made of it; "to use `hand' for `worker' or `ten sail' for
           `ten ships' or `steel' for `sword' is to use a
           synecdochic figure of speech" [syn: synecdochic,
           synecdochical]