metonymy

n. figure of speech that uses one object in place of another related concept (e.g., using "the throne" to refer to the monarchy)

In rhetoric, metonymy is the use of a word for a concept with which the original concept behind this word is associated. Metonymy may be instructively contrasted with metaphor. Both figures involve the substitution of one term for another. While in metaphor, this substitution is based on similarity, in metonymy the substitution is based on contiguity.
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Noun
1. substituting the name of an attribute or feature for the name of the thing itself (as in `they counted heads')
(hypernym) trope, figure of speech, figure, image
(hyponym) metalepsis
(class) voice

(n.)
A trope in which one word is put for another that suggests it; as, we say, a man keeps a good table instead of good provisions; we read Virgil, that is, his poems; a man has a warm heart, that is, warm affections.
  

n.
علم کلام ميں ايک صنعت, مجاز